On Thursday I received my RS-1 (bailed on the AVS buy and located one at a great price in the mid-west), along with this months copy of Home Theater magazine. It has a 1080P projector shootout between the RS-1, Mits HC5000U, and the Sony Pearl. It's a good review, and high marks are given to the RS-1 on image quality, but the reviewer found it loud, and preferred the Pearl for a living room home theater. Two brief quotes:

"The JVC is downright loud, easily overpowering the other projectors and disc players with its noise".

"With high quality sources, the JVC renders a beautiful image, but it is also the biggest, loudest, most expensive projector, and it spills light around the screen. The Sony is the quietest, most versatile projector, which would make it a better choice for a living room home theater setup like mine".

I bought it sight and sound unseen; while both my wife and I are fussy about extraneous noise, the multiple postings along the line of "I sit a few feet from it and can barely hear it with the sound off" convinced me that it would be fine. Unfortunate timing on the HT review. I'm not sure how to account for the disparity in reactions; perhaps there are unit to unit variations, maybe its personal thresholds of acceptance, or possibly the room can be a factor - other than the carpet, we have sheet rock walls and ceiling.

I love the image - its super detailed and punchy (100" HiPower, near max throw, low lamp). I see hand puppets, but the blacks are very good. This our first projector, so we don't have anything to compare it to. It will take a few days to sort out the noise. We are far from being audiophile purists, but if any home theater sound system added a tenth of this level of background noise (granted, only audible in quiet passages), it would be obviously unacceptable. I may bail for the Pearl.

Did you find the noise to be a problem with your unit before you read the review?

Yup. Fired it up about an hour before what I read matched my reaction. At first, I hoped it had defaulted in high lamp, but no luck there.
FWIW, we mute commercials, and I find co-workers obsessively clicking and tapping pens during meetings an irritant worth mentioning.

Did you find the noise to be a problem with your unit before you read the review?

I think the review came out the same time he rec'd his unit...at least that is my understanding from a post in one of the other JVC threads.

That's the first time I've heard of anyone giving the pearl the nod over the Mitsubishi for noise. Most things I've seen say the Mits is the quietest projector around.

Are you using the high altitude setting? I was surprised at how noisy the RS-1 can get with HA + high bulb settings both enabled. With HA disabled and normal bulb settings though the RS-1 is usually very quiet. I had a chance to inspect a 2nd batch RS-1 a few weeks ago and found it noticeably quieter than my 1st batch RS-1 so I think there is some unit to unit variation.

Kevin,
I was in the 2nd batch. I had a Sony 10HT before the RS1. The Sony was advertised at 30db at normal bulb setting. My RS1 is much quieter. It is mounted directly overhead, 13" down from an 8' ceiling (same spot as the Sony). Unless there is dead silence in the movie, I do not hear it; nor do my guests. I am sure this is a unit by unit difference. FWIW - I find the RS1 is a little louder when first turned on. I find that after a minute or so, it quiets down a lot - to the levels described.
Regards,
Dom

My RS1 is no more than 2 ft from wife and my heads, and I never hear it except when it starts up before any pic is on the screen. Listen to the Optoma HD81 is you want to hear LOUD. And as Mark said, everything I've read says that the Mits is the quietest.

and my heads

How many do you have?? :) :)

How many do you have?? :) :)If he is normal, just two :D.

My RS1 measures 47-49 dB at 12 inches in normal (low bulb power) bulb mode, which is less than the vast majority of PJs out there. However, the quality of the sound does seem to have a small component of mechanical noise (vs just the woosh of air) which makes it seem louder than my meter would indicate.

That being said, it is quieter than most of the PJs I have seen over the years. If you want something totally silent, you have very few options, and they will all involve other compromises compared to the RS1.

In all PJs, they can vary from one unit to the next. It sounds as if the review unit quoted in the first post may have been louder than is typical, but who knows?

Glenn

My RS1 is no more than 2 ft from wife and my heads, and I never hear it except when it starts up before any pic is on the screen. Listen to the Optoma HD81 is you want to hear LOUD. And as Mark said, everything I've read says that the Mits is the quietest.


I agree, I went from a HD81 to the RS-1 and the sound difference is night and day.
When I first would start the 81 I could hear it was "on" from about anywhere in the room.
Now even if I am close to the RS1 I have to look at the indicator light to make sure its "on" in the warm-up stage when there is no light coming out of the lens.

Being a DLP user for the last 4 years, I am totally happy with the sound level.
Obviously this projector reviewed must defective.

Tony

Mine sits 6 feet behind us on a rear shelf> I have been watching just video for two days.(sound system not hooked up yet but had to check out the picture). I do not find the fan distracting at all, as a matter of fact I was pleasantly surprised as to how quiet it is (normal mode) .

The SOTA $20K Marantz DLP is big and noisy too. I guess I'm not going to buy it now either. Thanks!

We are really discussing is a lady reviewers opinion (if remember reading it correctly at the bookstore).
Was this same miss who also recommended the film Eragon. Based upon her strong recommendation I bought a copy.
The story revolves around sweet, cutesy very feminine dragon.
(The situation is getting desperate when you combine this type of fluff with Ms. Stacey Spears banal column in Widescreen Review).

It’s important to match the furnishing size to the room size. For a small room don't purchase large overstuffed sofas, chairs, large speakers or large subwoofers. Or even front projectors at all. Get a flat panel instead. (Boys and their balanced practical logic).

My crystal ball says the projector did not match her small expensive east coast room/apartment. In the future I plan to stick to the boy’s opinion at Home Theater Magazine.

Of far more interest was the male reviewers comment as to why the JVC image is so addicting, especially when watching House. One addict watching another, I guess! :)

If you actually read the latest Home Theater issue, you will see that the side box with the "downright loud, easily overpowering the other projectors and disc players with its fan noise" comment was written by John Higgins. The lead author was Geoffrey Morrison, and Adrienne Maxwell also contributed (adding her own side box that found the RS-1 loud and not the best choice for a living room home theater). We should skip the gender and/or owner blame game and focus on what is actually going on here.

The comments from millerwill, DomNY, and especially the following from tjgar:

"even if I am close to the RS1 I have to look at the indicator light to make sure its "on" in the warm-up stage when there is no light coming out of the lens".

make it abundantly clear to me that this is NOT an issue of personal irritatability thresholds; it is CLEARLY unit to unit variation.

Sound requires motion. To the best of my knowledge, there are only two active moving parts in the RS-1 - the main fan and the optics block fan. The airflow requirements of the main (lamp cooler) fan have to be many times higher than than those of the optics block, so that is where I would start.

Looking at the Cine4home RS-1 review:
http://www.cine4home.com/reviews/projectors/JVC-HD1/HD1Test.htm
the main fan is clearly visible as a Nidec Beta SL. Not sure if it is a 90 or 120 mm. I googled the model, and found the 90 mm going for a whopping $1.88 in 40 piece quantity:
http://www.evertek.com/viewpart.asp?auto=25068
Hardly a premium fan.
I also found reports from people trying to silence computer cases, who generally regard the Nidec Beta SL as an offender to be swapped out for something quieter:
http://episteme.arstechnica.com/6/ubb.x?q=Y&a=tpc&s=50009562&f=77909585&m=178099784
On the Nidec Japanese web site, I found data sheets for the 90 mm:
http://episteme.arstechnica.com/6/ubb.x?q=Y&a=tpc&s=50009562&f=77909585&m=178099784
but I would need to get the specific part number off the RS-1 fan to be sure.

As an aside, the RS-1 dissipates 280 watts. At room temperature and pressure, 0.83 liters per second of airflow are required per watt of power for a delta T between inlet and outlet air of 1 degree C. The RS-1 would require 16 lps (30 cfm) to acheive a delta T rise of 15 C (27 F), but I have yet to measure the outlet air temp.

I am heavily involved with the diagnosis and elimination of vibration and resonances in my work life. I presented a paper at my alma mater (MIT) a couple of years ago on an air bearing, constant velocity scanning stage with a resolution of 31 picometers. We balance air bearing spindles to 0.001 gm-cm.
I know about vibration.
When I examine the RS-1, I notice that the noise is NOT the airflow itself, but rather a distinct droning case vibration that is easily felt by hand and is most pronounced directly above the main fan. I think I will put a low noise piezo accelerometer on the case and look at the output on a spectrum analyser - I expect I will see a driving frequency at the fan rotation speed, together with a forest of plastic case modal resonances. A look at the Cine4home review photo shows four blocks of white foam that are intended to vibration isolate and mount the fan, and which appear to bear against the outer case. I think that the unit to unit noise variation is either due to a badly balanced, cheap Nidec fan, or differing quality of vibration isolation of the fan. If one part (the wire mesh, say) provides a direct path from the fan body to the case, the isolation of the white blocks is substantially compromised.

I will measure things, and ask JVC Pro if they would consider taking a look at this (I would even pay). I don't want to personally intervene, swap fan, etc, because that would void my warranty. Given the Home Theater review, JVC may lose sales over this, so some attention to this issue would seem in order. Certainly, there is NO WAY Home Theater's comments (or my observations) can be squared with:

"even if I am close to the RS1 I have to look at the indicator light to make sure its "on" in the warm-up stage when there is no light coming out of the lens".

What the above observation says is that the RS-1 CAN BE (and probably usually is) an extremely quiet unit. Quality control is all about understanding the root causes of variation and driving them down in a reproducible manner. I'll bet they can do this.

Kevin

My RS-1 isn't loud and it sits around 2 feet above my head. My Toshiba HD-A1 that is hmm, 7 feet away from me is louder than the RS1.

I'm pretty aware when it comes to this stuff so it isn't like I just have some great tolerance for fan noise and can block it out. I would agree that it must be a unit to unit variance and that is why yours and that one in the review were found to be noisy.

The SOTA $20K Marantz DLP is big and noisy too. I guess I'm not going to buy it now either. Thanks!
Ah, good idea...Dismiss yet another projector without ever hearing or seeing it. Let's be honest here...You are never going to actually BUY any front projector, are you?
We are really discussing is a lady reviewers opinion (if remember reading it correctly at the bookstore).
The 2 quotes in the first post were from 2 different "auxiliary" reviewers. The first quote was by John Higgins while the second one was from Adrienne Maxwell.
My crystal ball says the projector did not match her small expensive east coast room/apartment.
Incredible insight! :rolleyes: I'm sure that the "versatile projector (Sony) with ample adjustments to fine-tune the picture to your taste" and that the JVC is the "loudest, most expensive projector, and it spills light around the screen" had absolutely nothing to do with her decision. As you continue to insult anyone who disagrees with your assessment, she must have judged the projectors based on how it looked inside of her small east coast apartment, right? Oh, and I guess you have some inside information here as to where she lives and whether it is a home, condo, or apartment, heh?
Of far more interest was the male reviewers comment as to why the JVC image is so addicting, especially when watching House.
Of course it was! As long as the person agrees with YOU, then he is perceptive, insightful, and "interesting." Why don't you just take the plunge and actually BUY a front projector and spend time with it rather than living vicariously from those who have?

rlindo: I have the RS-1 next to an HD-A2, and the RS-1 seems to be about 3X louder (entirely subjective, and I am aware perception is logarithmic). Another case for unit to unit variation (aka quality issues).

Our RS1 sits three feet above and right behind our heads. Can't hear it. I need to get within about a foot before I can hear it at all. I'm pretty sensitive to projector noise, even purchased a whisperflow for my 7205. Another vote for unit to unit variation.

I guess I don't get the issue with the noise of the RS1. The average volume of a movie more than drowns out any noise that it makes in my room. Of course, I do have unit at the back of the room, and it's in front of a large bank of RPG Diffractals (see pictures in my HT link). Although, I don't know if the Diffractals would help with it's noise or not.

my rs1 is noisy too, when i listen for it. i don't even want to know what the sound meter might show.
i can hear it about 2.5 feet above and maybe 2.5 feet behind head.
i hear it. i can hear my rs1 from 20 feet away. my equipment is in the front of the room. if i stand there to fiddle with some setting on a source or the receiver, etc. i can hear the rs1. i'm not deaf!
ears are really generally very good. anyone who says they don't hear it is either really far away or have low hearing or they are exagerating about not hearing their rs1. you know exagerating like my pj is better than yours because .... and it is silent.
the real point in my mind has been so what? are people bothered, distracted. no. even close up the rs1 is not distracting. it gets forgotten once the movie begins.
i also have my theater like a bat's cave. every single thing in front of the seats is matt-black ceiling to floor. still there is reflected light that is easily seen. eyes too are really very good. i think even most who are considered blind would detect this light. that light gets forgotten also.
i think the rs1 is great because the pj is not distracting in any way. just try it, go ahead and enjoy. turn up the audio and forget the noise from the pj. enjoy watching some dvd, hddvd, br or hd cable. one of my new favorite things is to watch concerts in hd, this pj puts you there. i just okk mine out of the box and turnned it on. and wow! it is point and shoot pj that also happens to have professional specs.
but i digress.
don't worry, this pj takes care of itself in the theater very well. it makes noise, but not too much.

We are really discussing is a lady reviewers opinion (if remember reading it correctly at the bookstore).
Was this same miss who also recommended the film Eragon. Based upon her strong recommendation I bought a copy.
The story revolves around sweet, cutesy very feminine dragon.
(The situation is getting desperate when you combine this type of fluff with Ms. Stacey Spears banal column in Widescreen Review).

It’s important to match the furnishing size to the room size. For a small room don't purchase large overstuffed sofas, chairs, large speakers or large subwoofers. Or even front projectors at all. Get a flat panel instead. (Boys and their balanced practical logic).

My crystal ball says the projector did not match her small expensive east coast room/apartment. In the future I plan to stick to the boy’s opinion at Home Theater Magazine.

Of far more interest was the male reviewers comment as to why the JVC image is so addicting, especially when watching House. One addict watching another, I guess! :)

If only she'd reviewed the projector while barefoot and pregnant, then the little lady would be doing something right...right?

Kevin, excellent post containing some great information and "probable cause" of the variation in fan noise from unit to unit. Even though I don't find the noise from my RS-1 as particularly bothersome, I would have no problem voiding the warranty to replace the fans in my unit in order to quiet it down. Would it be as simple as finding a better built, quieter fan that has at least the same cfm rating (or better), and then taking care to shock mount it properly?

The different noise levels being experienced appear to be, as demonstrated here last night, the result of differences between RS-1's. We measured three RS-1's last evening and all had different measurements. The low at one foot was 42 dB and the high was 53 dB, so differences do exist between units. I think Kevin McC. makes a solid argument for the likely cause of varying noise levels.

In all three cases, the owners here were satisfied with these levels.

Jim

ears are really generally very good. anyone who says they don't hear it is either really far away or have low hearing or they are exagerating about not hearing their rs1. you know exagerating like my pj is better than yours because .... and it is silent.

Maybe this is what you are hearing from those who are reporting that our projectors are quiet(pun intended), but that is not the case. i am not bragging when I say mine is quiet. I can't imagine that anybody who hears my projector would come anywhere near to thinking it is loud. I believe that yours is louder. As several people have theorized, there seems to be variance from unit to unit.

From Jim's post above, it sounds like kevin's may be a bad unit with above average fan noise. I would take it back and exchange it with your dealer. Don't settle for a noisy unit.

My sound level meter is the RS digital one. I don't believe it registers anything below 55db. With that said, even with the meter right up against my HD1 at low lamp level, it doesn't register anything. Like others have stated, if all is quiet in the room, I can hear the fan. However, the fan noise disappears when I have any other sound at all. In fact, I think my AC noise through the vents in the room are just as loud.

Bob: Thanks. Active intervention to address the issue should be approached in a layered fashion:

The first plan would be to examine the vicinity of the fan to better understand JVC's original intent for vibration isolation, and see if there are any obvious small errors that are preventing it from being effective. All structural paths from the fan body to the case (almost certainly the sounding board) should be compliant and absorptive. It may be as simple as a slight dimensional offset that permits a rigid bypass of the isolator.

The next level would be to alter or add isolation elements. This preserves all of the original design intent that led to the selection of the Nidec fan, and so doesn't monkey with heat transfer. The silent computer case community has, for example, silicone gaskets that fit standard fan sizes:
http://209.47.233.50/acb/showdetl.cfm?&DID=8&Product_ID=269&CATID=7
Bear in mind that this gasket is 2.5 mm thick, and even when partially compressed, there may be a dimensional conflict.
Another possibility would be to beplace the four white triangular prisms of presumeably vibration isolating material (visible in the Cine4home review) with equivalent sized pieces of something better. One such material would be sorbothane. We use bushing mounts with this visco-elastic compound to prevent fan vibration in our servo control systems from coupling into our high precision stages. It comes in a variety of forms, including gaskets, screw mount bushing isolators, and solid blocks:
http://www.sorbothane.com/PDF/StandardProduct.pdf

The next level would be to consider fan replacement. High-end fans with sufficient flow rates and very low noise levels are available from folks like this:
http://209.47.233.50/acb/showdetl.cfm?&DID=8&CATID=7&ObjectGroup_ID=58&OBS=10&Move=Next&count=7&Pcount=7
The problem is, it is not enough to simply read a flow rate specification. If you examine the Nidec PDF link in my earlier post, you will see how they provide graphs relating air flow rate (Q, in cubic meters per minute) to fan speed and back pressure. With enough back pressure (restriction), the air spills around the blades and the flow is zero (followed shortly by your thermal alarm tripping). This data is not obvious in the QuietPC spec sheets, and the fan blade design appears to allow a lot of spillage at high back pressure. We cannot quantitatively determine the back pressure presented by restrictions in the path both before and after the fan, but we do have one very fundamental and easily measureable metric - the temperature of the exiting air. As far as I know, if you were to replace the fan, and the exiting air temperature was no hotter than that of a stock RS-1, you should be golden.

Before beating this theme any further into the ground, it's important to think about fan voltage. Most fans of this type are nominally 12 volt devices that vary their speed with the applied voltage. JVC undoubtedly ups the voltage for High Lamp and High Altitude modes (more accurately, they drop it to the lowest value for Normal mode). A voltmeter would quickly put a value on the three modes. If one were to substitute an ultra-low noise fan for the current model, an in-line resistor could be used to dial down the voltage seen by the fan, and provide an independent control of fan speed. For example, you could go in with an oversize fan, confirm that the exit air was cooler than that of a stock RS-1, and then dial down the voltage to match the current performance, probably at a lot lower sound level.

If the problem is fan intrinsic balance, the fan should be replaced. If the problem is compromised vibration isolation, that needs to be addressed.

The original response of owners of quiet RS-1's to comments by people who found them noisy was to assume that we were all whiners. I think it has now become clear that the real culprit was an unexpected and wide unit to unit variance. If anyone is bold enough to attempt a cure, do let myself and others know (PM if you are nervous). At the least, a specific (from the label) model number for the Nidec fan would be valuable.

Kevin

My experience has also been that the RS1 is not all that quiet as I'd posted here. (http://www.avsforum.com/avs-vb/showthread.php?p=10435477#post10435477)
If you have moderate ambient noise, you will not hear it ... but if you have a tombstone like I do, you will.

"9db is significant."

Esp. when it is 11db.....

From a subjective standpoint 10dB is heard as twice as loud.

Shawn

The different noise levels being experienced appear to be, as demonstrated here last night, the result of differences between RS-1's. We measured three RS-1's last evening and all had different measurements. The low at one foot was 42 dB and the high was 53 dB, so differences do exist between units. I think Kevin McC. makes a solid argument for the likely cause of varying noise levels.

In all three cases, the owners here were satisfied with these levels.

Jim
This is the first evidence that there are indeed variations in the SPL generated by the fan in the RS1 under identical conditions. 11db is very significant and outside any normal unit-to-unit variation. The customer should not have to be making measurements, but instead exchange the unit. Is this practical? How is the JVC service?

Once again patience is a virtue. I may spring for the Sharp 20000. But the rumored Infocus appears tempting too! This market sure is turbulent (like never before). In a perverse sort of way I thank JVC for not be able to deliver.

So Bob, like what's wrong with the new $10,000 Sharp 20000 you just received?

So Bob, like what's wrong with the new $10,000 Sharp 20000 you just received?
It's not the $10k Sharp 20k, it's the $2k Sharp 12k Mk II. It is louder than the RS-1, but I might try fixing the fan noise in that unit first before tackling the RS-1. As far as other things wrong with it, I'll explain more later in another thread. The short story - It is an incredible bargain for $2k!

Mine's pretty noisy too. It's about 5' above and 3' behind my head. Low lamp is acceptable... definitely audible in quiet passages. Hi lamp is unworkable. Simply can't stand it. But the new house has a projection booth and that's where I'll be in 2 months (I hope!) so it really doesn't matter to me.

The AC vents in my room are almost silent. You really cannot tell if it is on, unless you put up your hand to feel the air flow.

I am thinking that there must be unit to unit variation. The one I heard in a local shop, well, I did not hear it. I did not listen really carefully, but it was quiet enough that I did not really worry about listening closely.

Best Regards,
Doug

It's not the $10k Sharp 20k, it's the $2k Sharp 12k Mk II. It is louder than the RS-1, but I might try fixing the fan noise in that unit first before tackling the RS-1. As far as other things wrong with it, I'll explain more later in another thread. The short story - It is an incredible bargain for $2k!

Here is the reviewer rating of the $10K Sharp XV-Z20000 fan noise:
Between the two lamp settings, Bright and Eco-Quiet, the first throws a picture bright enough for a well-lit room but suffers from considerably more fan noise than Eco-Quiet (which was already pretty audible).

http://www.soundandvisionmag.com/hdtvs/2266/shootout-three-1080p-front-projectors-page6.html

It's not the $10k Sharp 20k, it's the $2k Sharp 12k Mk II. It is louder than the RS-1, but I might try fixing the fan noise in that unit first before tackling the RS-1. As far as other things wrong with it, I'll explain more later in another thread. The short story - It is an incredible bargain for $2k!

I agree. The Sharp 12K is an excellent performer for a 720P DLP. Is it really down to $2K?

The Sharps have been typically a bit louder than some of their competition. My RS1 measures much lower in noise volume than any of the Sharps I have measured.

Glenn

Kevin,

It is nice to read input regarding this issue from someone with your level of expertise in damping noise from mechanical devices. Keep it up.

Glenn

To put some of the dB measurements into perspective:

I measured the ambient noise in my home at midnight with everything shut down. I don't remember for sure what the reading was, but if I recall it was either 37dB or 32 dB ( and I think it was 37 dB). When a car drove by in front of the house the meter picked up the volume and registered an increase. A fridge 30 ft away also registers an increase in dB on the meter. A PC in another room 40' away behind a closed door also increases the measurement.

I picked a time for the measurement when the HVac, fridge, computer, and everything else in the house was off. The house was virtually silent.

Glenn

To be clear, mine is quiet in normal mode but objectionable to me in high lamp mode. I would pay for a new bulb before using the high lamp.

Even in low mode I'm going to have to put this thing in a hushbox (dead-silent theater). It's a total non-issue until there is quiet on the movie soundtrack, at which point it's not just noticeable, but obvious that the projector is noisy.

It really is about the chassis vibrating (or the fan itself). It doesn't help that because it's front-venting, the noise is directed right at the audience. While the A2/PS3 are almost as bad, they at least vent away from the audience and the sound is dissipated on the fabric-covered wall of my theater.

I'm wondering if this is something that would be worth a warranty return? My first-batch unit needs a firmware upgrade anyway.

Alternatively what can be done to minimize (or damp) the vibration? I remember a test run on a padded chair made it less noticeable. Perhaps those using ceiling mounts are actually having less transmission of the vibration into the case (because the energy is being absorbed by the mount)?

(I'd still rather have this PJ, and the expense of a hush-box, because even the RS-1 still isn't quite 'there' with what I want for black level and contrast, but it's the best I can afford.)

The Sharp 12K is an excellent performer for a 720P DLP. Is it really down to $2K?Yup. With all the new superior PJ's out there for just a few more bucks, it's a tough market for the older 720 units. I paid $10K for my Marantz a few years ago, and now the RS1 trounces it for half the price.

I suspect a large amount of the 'unit-to-unit' differences is really the noise floor of the room you are using it in. Most non-soundproofed rooms have a high noise floor!

If you have a soundproofed room you can absolutely, unequivocally hear the fan during quiet passages. Whether or not this bothers you is a personal decision. The reality is that very few projectors are quieter, even today.

Andy K.

This is a terribly well thought out, and fair assessment, without any bias that I can see. My greatest compliments Kevin.


John


If you actually read the latest Home Theater issue, you will see that the side box with the "downright loud, easily overpowering the other projectors and disc players with its fan noise" comment was written by John Higgins. The lead author was Geoffrey Morrison, and Adrienne Maxwell also contributed (adding her own side box that found the RS-1 loud and not the best choice for a living room home theater). We should skip the gender and/or owner blame game and focus on what is actually going on here.

The comments from millerwill, DomNY, and especially the following from tjgar:

"even if I am close to the RS1 I have to look at the indicator light to make sure its "on" in the warm-up stage when there is no light coming out of the lens".

make it abundantly clear to me that this is NOT an issue of personal irritatability thresholds; it is CLEARLY unit to unit variation.

Sound requires motion. To the best of my knowledge, there are only two active moving parts in the RS-1 - the main fan and the optics block fan. The airflow requirements of the main (lamp cooler) fan have to be many times higher than than those of the optics block, so that is where I would start.

Looking at the Cine4home RS-1 review:
http://www.cine4home.com/reviews/projectors/JVC-HD1/HD1Test.htm
the main fan is clearly visible as a Nidec Beta SL. Not sure if it is a 90 or 120 mm. I googled the model, and found the 90 mm going for a whopping $1.88 in 40 piece quantity:
http://www.evertek.com/viewpart.asp?auto=25068
Hardly a premium fan.
I also found reports from people trying to silence computer cases, who generally regard the Nidec Beta SL as an offender to be swapped out for something quieter:
http://episteme.arstechnica.com/6/ubb.x?q=Y&a=tpc&s=50009562&f=77909585&m=178099784
On the Nidec Japanese web site, I found data sheets for the 90 mm:
http://episteme.arstechnica.com/6/ubb.x?q=Y&a=tpc&s=50009562&f=77909585&m=178099784
but I would need to get the specific part number off the RS-1 fan to be sure.

As an aside, the RS-1 dissipates 280 watts. At room temperature and pressure, 0.83 liters per second of airflow are required per watt of power for a delta T between inlet and outlet air of 1 degree C. The RS-1 would require 16 lps (30 cfm) to acheive a delta T rise of 15 C (27 F), but I have yet to measure the outlet air temp.

I am heavily involved with the diagnosis and elimination of vibration and resonances in my work life. I presented a paper at my alma mater (MIT) a couple of years ago on an air bearing, constant velocity scanning stage with a resolution of 31 picometers. We balance air bearing spindles to 0.001 gm-cm.
I know about vibration.
When I examine the RS-1, I notice that the noise is NOT the airflow itself, but rather a distinct droning case vibration that is easily felt by hand and is most pronounced directly above the main fan. I think I will put a low noise piezo accelerometer on the case and look at the output on a spectrum analyser - I expect I will see a driving frequency at the fan rotation speed, together with a forest of plastic case modal resonances. A look at the Cine4home review photo shows four blocks of white foam that are intended to vibration isolate and mount the fan, and which appear to bear against the outer case. I think that the unit to unit noise variation is either due to a badly balanced, cheap Nidec fan, or differing quality of vibration isolation of the fan. If one part (the wire mesh, say) provides a direct path from the fan body to the case, the isolation of the white blocks is substantially compromised.

I will measure things, and ask JVC Pro if they would consider taking a look at this (I would even pay). I don't want to personally intervene, swap fan, etc, because that would void my warranty. Given the Home Theater review, JVC may lose sales over this, so some attention to this issue would seem in order. Certainly, there is NO WAY Home Theater's comments (or my observations) can be squared with:

"even if I am close to the RS1 I have to look at the indicator light to make sure its "on" in the warm-up stage when there is no light coming out of the lens".

What the above observation says is that the RS-1 CAN BE (and probably usually is) an extremely quiet unit. Quality control is all about understanding the root causes of variation and driving them down in a reproducible manner. I'll bet they can do this.

Kevin

What I noticed tonight turning on the RS-1 is that my unit has the fan noise level pretty much constant from start to turn off. It never gets louder or quieter unless I manually mess with the bulb settings or HA settings. But I see some people say it actually quiets down after startup. Perhaps the problem with the noisy RS-1's is some problem that is preventing them from actually going to a lower fan speed?

(My room is a pretty steady 65f temp, lots of ventilation, so I doubt it's heat.)

What I noticed tonight turning on the RS-1 is that my unit has the fan noise level pretty much constant from start to turn off. It never gets louder or quieter unless I manually mess with the bulb settings or HA settings. But I see some people say it actually quiets down after startup. Perhaps the problem with the noisy RS-1's is some problem that is preventing them from actually going to a lower fan speed?

(My room is a pretty steady 65f temp, lots of ventilation, so I doubt it's heat.)
Mine definitely does not change speed during use FWIW.

Even in low mode I'm going to have to put this thing in a hushbox (dead-silent theater). It's a total non-issue until there is quiet on the movie soundtrack, at which point it's not just noticeable, but obvious that the projector is noisy.

It really is about the chassis vibrating (or the fan itself). It doesn't help that because it's front-venting, the noise is directed right at the audience. While the A2/PS3 are almost as bad, they at least vent away from the audience and the sound is dissipated on the fabric-covered wall of my theater.

I'm wondering if this is something that would be worth a warranty return? My first-batch unit needs a firmware upgrade anyway.

Alternatively what can be done to minimize (or damp) the vibration? I remember a test run on a padded chair made it less noticeable. Perhaps those using ceiling mounts are actually having less transmission of the vibration into the case (because the energy is being absorbed by the mount)?

(I'd still rather have this PJ, and the expense of a hush-box, because even the RS-1 still isn't quite 'there' with what I want for black level and contrast, but it's the best I can afford.)

I know exactly what you mean! I thought of putting this in a box also but the manual claims that the PJ needs to be provided 150mm of space above, 300mm on each side and 200mm behind it. 150mm is about 6 inches, so with these kind of clearances, we'd have one really huge box!!
Since the PJ is ceiling mounted in my case, I am thinking of just putting a padded wooden "shield" below and on the 3 sides of the PJ with the top left open for heat dissipation. I can then also add a SilenX fan like the IXP-76-18 (http://www.silenx.com/ixtremaprofans.asp?sku=ixp-76-18) to provide circulation near the top. This will probably help, but I still have to figure out how exactly to build and mount this "open box". :)

I'd like very much to get this fan issue dealt with. Who should I (we) talk to at JVC to get the ball rolling on this, and firmware update issues (JVC reps, hint hint)?

wildfire99: I wouldn't hold out much hope of a firmware update beyond the 061 update at the second wave. As to addressing the anomalous noise issue, I have already sent a PM and will be calling JVC soon, so I'll advise folks on this thread as to my progress (or lack thereof).

Kevin

Looks like I'm another of the lucky ones with a very quiet RS1. My HT is soundproof, heavily treated and there is no other equipment in the room - I also have to look at the lens to see if it turned on when I first hit the remote.

I had originally thought it had something to do with the room treatments (reflective rooms amplifying the problem) but there is obviously something else going on if, as someone mentioned earlier, you can hear it from across the room while standing in front of an equipment rack. That is a massive difference.
Craig.

If only she'd reviewed the projector while barefoot and pregnant, then the little lady would be doing something right...right?
Not at all. Men and women do think differently and have different priorities. Cerebrate those differences as we meant to complement one another.
So like just what are your credentials? I notice you like Hamlet and Mel Gibson. So too does my wife:)
Have a nice day!

strange_brew: "I also have to look at the lens to see if it turned on when I first hit the remote."

One more strong indication that this is a quality problem, not an owner problem. The RS-1 is clearly capable of outstanding noise levels. Watching The Searchers last night, the drone from my RS-1 was clearly audible not just in the silent passages, but during all of the dialog scenes. We need this fixed. Thanks for your input.

Kevin

My theater is totaly soundproof, I have the RS1 in my soffit with the front cut out the width of the projector so that the exhaust and intake can take air in and out easily. When the projector is fired up, I can't hear it or see any thing on the screen, I have to look into the lens to see the light coming out of the lens to make sure it's on. It's very quiet and the blacks incredible.

Keep up the great work Kevin! Your dedication to this noise issue is appreciated by all who have this problem. Hope JVC helps you and all others solve this situation.

I know exactly what you mean! I thought of putting this in a box also but the manual claims that the PJ needs to be provided 150mm of space above, 300mm on each side and 200mm behind it. 150mm is about 6 inches, so with these kind of clearances, we'd have one really huge box!!


Well that would be a bummer, since I've been considering a hush box for the JVC (because it's looking like it would have to be several feet above my head, in my room).

But, I would think those recomendations for clearance are the vent requirements for the projector itself. Many hush-boxes employ whisper-quiet fans to vent the heat from the hushbox, which I would presume would reduce the need for all that clearance. (?)

That's what I figured. As long as you have air flow in the box, who cares? There's an intake in the front, and a filter on the bottom side (I suppose another intake). It exhausts out the front also. You may need some special ducting for the front but... that's not hard.

Edit: Here's a quick render of what I had in mind for a box:

http://img259.imageshack.us/img259/1975/rs1boxtopwg5.th.jpg (http://img259.imageshack.us/my.php?image=rs1boxtopwg5.jpg)

http://img515.imageshack.us/img515/2825/rs1boxpspsa0.th.jpg (http://img515.imageshack.us/my.php?image=rs1boxpspsa0.jpg)

loud in normal lamp ?LOL !!!!!!!!!!!!
it's not at all and punchy with boosted RGB.

case closed.

That's what I figured. As long as you have air flow in the box, who cares? There's an intake in the front, and a filter on the bottom side (I suppose another intake). It exhausts out the front also. You may need some special ducting for the front but... that's not hard.

Edit: Here's a quick render of what I had in mind for a box:

http://img259.imageshack.us/img259/1975/rs1boxtopwg5.th.jpg (http://img259.imageshack.us/my.php?image=rs1boxtopwg5.jpg)

http://img515.imageshack.us/img515/2825/rs1boxpspsa0.th.jpg (http://img515.imageshack.us/my.php?image=rs1boxpspsa0.jpg)


Hmmmm..... make sure you have enough room to get your paws in there to adjust the optics andhorizontal and vertical shift wheels which are located just under the lens on the bottom

loud in normal lamp ?LOL !!!!!!!!!!!!
it's not at all and punchy with boosted RGB.

case closed.

Did you read the whole thread???

loud in normal lamp ?LOL !!!!!!!!!!!!
it's not at all and punchy with boosted RGB.

case closed.
I really don't understand this post. What case? Whose case? LOL?? What's funny? It's OOLF.

I really don't understand this post. What case? Whose case? LOL?? What's funny? It's OOLF.I think he is trying to be sarcastic. But who knows.

That's what I figured. As long as you have air flow in the box, who cares? There's an intake in the front, and a filter on the bottom side (I suppose another intake). It exhausts out the front also. You may need some special ducting for the front but... that's not hard.

Edit: Here's a quick render of what I had in mind for a box:

http://img259.imageshack.us/img259/1975/rs1boxtopwg5.th.jpg (http://img259.imageshack.us/my.php?image=rs1boxtopwg5.jpg)

http://img515.imageshack.us/img515/2825/rs1boxpspsa0.th.jpg (http://img515.imageshack.us/my.php?image=rs1boxpspsa0.jpg)
Nice! I think you might need to angle the pieces at the front on either side of the lens though, or you might end up clipping the sides of the image (depending on your zoom of course)

Nice! I think you might need to angle the pieces at the front on either side of the lens though, or you might end up clipping the sides of the image (depending on your zoom of course)

Angling those pieces might help with airflow, too.

Just guessing, but it seems like you might be more likely to get laminar flow along the surface instead of turbulent flow in the corner.

Best Regards,
Doug

Any consensus on whether the noise level is affected by its mounting orientation ?

I've had mine set upright on a stand and couldn't hear it all from 3 feet away. My HTPC is about the same distance and I definitely hear that !

Still, I am working on my room and will be mounting it inverted when the room is done. I hope the noise level is still unobtrusive then. The HTPC will be much further away from the seating area, however, so I won't have it drowing out any RS1 noise.

Mine is inverted and, as I have posted before, its very quiet. It wouldn't really matter to me if it were quieter - I can't hear it now anyway.

Darryl,
The unit being above and slightly behind is not ideal, as the sound coming from the fan is directed right at you. Having the proj slightly in front or directly overhead keeps the fan noise directed away from you, not at you. I moved my Sony 10HT from slightly behind me to just slightly in front of me for that reason.(The zoom lens made up for the difference) To give it an estimate in improvement, I would say more than a 25% drop in the level. My RS1 is now exactly where my 10HT was. Also for those that shelf mount these, remember vibrations are transferred to the shelf, which creates it's own noise. This was "brought home" to me when I bought an Apricorn 500 Gig Xpander drive for my SA8300 DVR. With the closet open, I could hear the unit hum. I picked it up and the noise dropped to almost zero. I have since put the drive on some 1/4 inch thick foam I had lying around. Created a dramatic improvement, as the vibration isn't transferred to the shelf.
Just my 2 cents and musings.

Everyone enjoy their RS1. I am.
Dom

Darryl,
The unit being above and slightly behind is not ideal, as the sound coming from the fan is directed right at you. Having the proj slightly in front or directly overhead keeps the fan noise directed away from you, not at you. I moved my Sony 10HT from slightly behind me to just slightly in front of me for that reason.(The zoom lens made up for the difference) To give it an estimate in improvement, I would say more than a 25% drop in the level. My RS1 is now exactly where my 10HT was. Also for those that shelf mount these, remember vibrations are transferred to the shelf, which creates it's own noise. This was "brought home" to me when I bought an Apricorn 500 Gig Xpander drive for my SA8300 DVR. With the closet open, I could hear the unit hum. I picked it up and the noise dropped to almost zero. I have since put the drive on some 1/4 inch thick foam I had lying around. Created a dramatic improvement, as the vibration isn't transferred to the shelf.
Just my 2 cents and musings.

Everyone enjoy their RS1. I am.
DomDom, good observation on the DVR. Being a bit of a HTPC geek, I have noticed that rubber HDD mount bushings make a HUGE difference in perceived "hum" from the computer due to the reduced vibration. Not sure it helps those with loud RS1's but a helpful observation nonetheless.

Any consensus on whether the noise level is affected by its mounting orientation ?

I've had mine set upright on a stand and couldn't hear it all from 3 feet away. My HTPC is about the same distance and I definitely hear that !

Still, I am working on my room and will be mounting it inverted when the room is done. I hope the noise level is still unobtrusive then. The HTPC will be much further away from the seating area, however, so I won't have it drowing out any RS1 noise.

I have it ceiling mounted using the Chief universal mount. The PJ is upside down, about 3 feet above my head and a couple of feet forward (so the fan vents away from me). I have also added rubber washers to prevent vibrations from being transmitted to the mount. It is still very audible during low volume segments (not just silent parts).

Incidently, this the second unit I received. The first one had a problem with a screeching fan (I think that it was scraping the sides), but this one is far better. However, it is definitely louder than the AE900 it replaces. Apart from the fan noise, the PJ is great so I've decided to just find a solution - am still mulling over the design in my head ...

I have it ceiling mounted using the Chief universal mount. The PJ is upside down, about 3 feet above my head and a couple of feet forward (so the fan vents away from me). I have also added rubber washers to prevent vibrations from being transmitted to the mount. It is still very audible during low volume segments (not just silent parts).

Incidently, this the second unit I received. The first one had a problem with a screeching fan (I think that it was scraping the sides), but this one is far better. However, it is definitely louder than the AE900 it replaces. Apart from the fan noise, the PJ is great so I've decided to just find a solution - am still mulling over the design in my head ...
A buddy of mine has the AE900. I can't believe you are saying it is louder than that - wow. I think everyone knows by now the variance among units is significant but that kind of difference is downright weird. It makes me wonder if the QA standards have been reduced to meet demand. Its obvious by now that JVC is unable to produce at a rate that will meet existing demand, so I can understand (but not condone) the inclination.


Craig.

The noise is mostly mechanical. A vibrating plasticky whirr, like a fan with poor bearings or off balance or something. I suspect it has more to do with assembly issues or poor fans, not necessarily a design flaw.

I went through a lot of problems to replace all my PC fans with 120mm 25db models, and they're not silent by any means, but they're an order of magnitude above (or more correctly, below) the RS-1's noise level, but when something starts to catch or get the case excited the wrong way, then they sound similar. If we could just do a fan swap with some rubber isolation mounts this would probably be a non-issue real fast.

Look at the fans in the cine4home teardown: http://www.cine4home.com/reviews/projectors/JVC-HD1/HD1Test.htm

The noise I hear that is annoying comes clearly from the left side (facing the lens). I can't tell if it's the large fan or the squirrel cage fan, but the latter is an ugly looking thing. I recorded some audio (very, very poor quality but the hand-held recorder is all I have right now) to show the relative noise and the type of noise for those interested.

Startup (http://www.theaterfood.net/galleries/avs/startup.mp3)
Close mic on left-side with fans (http://www.theaterfood.net/galleries/avs/closeup.mp3)
Ambient Audio Comparison (http://www.theaterfood.net/galleries/avs/ambient_audio.mp3)

The ambient audio one makes it sound worse than it is, but it's fairly omnipresent. It's not as bad as the last Infocus I had but it's still not what I would prefer to see at this stage of the projector game unless, hopefully, this is a rare-ish flaw that can be fixed.

Darryl,
The unit being above and slightly behind is not ideal, as the sound coming from the fan is directed right at you. Having the proj slightly in front or directly overhead keeps the fan noise directed away from you, not at you. I moved my Sony 10HT from slightly behind me to just slightly in front of me for that reason.(The zoom lens made up for the difference) Dom


And that will also make it BRIGHTER. Which is always good.

I contacted Tom Stites at JVC regarding the noise issue; he happened to be visiting my neck of the woods, and offered to get together and compare his unit and mine. He also offered to have me send my unit to California for an improvement attempt.

I drove over to meet him after work last night, and an A:B comparison showed that the level and tone of sound from both units was about the same. Despite being with JVC, Tom has only seen / heard a handful of RS-1's (why switch out your demo?), but he was pretty certain that they were all pretty similar to what we were hearing. That really lowered my hopes that my unit was anomalous and could be substantially improved. The California service offer is still open, but the down time and shipping risk doesn't seem worth what might be a modest or less improvement.

We did notice that the apparent sound level drops a lot when we held the RS-1 about a foot above the table, as opposed to being on it. I have it mounted on a shelf, and it appears that this exacerbates the noise output, possible reasons being the table acting as a sounding board, standing wave reinforcement due to reflections of the case vibrations off the table, or else the trapped air under the vibrating case acting as a resonant chamber. One simple ameliorative measure would be to make some short posts to elevate the mounting feet, and then add a layer of sound absorbant foam on the shelf. Another possibility would be to add a vertical lip around the perimeter of the shelf, also with sound absorbing foam. There could still be a vertical gap to allow air flow to the optic block filter fan. Finally, one could build a complete five sided cover, lined with sound absorbing foam, that would still be open on the front. This is a lot less effort than a sealed hush box with an optical glass window and additional fans.

Here's a source of sound absorbing foam, although it is pricey, and I don't know if run-of-the-mill open cell foam wouldn't do almost as well. It might be worth trying regular foam first.
http://209.47.233.50/acb/showdetl.cfm?&DID=8&Product_ID=48&CATID=6

This still leaves unresolved the reports of multiple posters who describe the RS-1 as virtually inaudible. I don't know how to reconcile this. Perhaps they are pole mounted without an adjacent surface, or maybe some units are anomalously quiet. On balance, I believe that I can make meaningful improvements without a service return or warranty voiding intervention, so that's what I will pursue. I do suspect that JVC could have made a quieter unit if that had been a high priority during the design phase. For what it's worth, they did drop the Normal fan speed subsequent to the pre-production prototypes, which led them to drop the dB spec from 27 to 25 dB (although I don't know the weighting or distance). If anyone should be considering active intervention, do bear in mind that the Nidec fan has a spped sensor that is monitored by the JVC, shutting things down if the fan speed slows below a threshold. This could be outfoxed with a little effort, but I thought it worth mentioning.

An unrelated tidbit is that the light output of the RS-1 is circularly polarized. This means that if you had two, and mounted an achromatized quarter wave plate in front of the lens, you could do 3-D without the 50% light loss you get with linear polarizers. Very cool, although with limited content, why bother? I have a library of 3-D home slides, but the added expense and complexity would be a bit much. I know this stuff cold, but in the interests of space, check Wikipedia if you want details on quarter wave plates and such.

JVC is serious about continuous improvement, and some interesting models are in store, albeit not imminently.

My thanks to Tom for the get-together.

Kevin

"This still leaves unresolved the reports of multiple posters who describe the RS-1 as virtually inaudible. I don't know how to reconcile this."

Different noise floors in each others various rooms?

Shawn

Craig,

"A buddy of mine has the AE900. I can't believe you are saying it is louder than that - wow.""

Depending upon how it is setup the AE900 can be pretty quiet or it can be fairly loud. In low power table top mode it is very quiet. Inverted it gets a bit louder, and louder yet in high power or high altitude modes. Also the DI in them makes noise and that seems to vary unit to unit.

So unless one knows how the AE900 is being run just comparing against it as a baseline is not very useful.

I am hoping the JVC is no louder then the AE900 in inverted mode.

Shawn

Craig,

"A buddy of mine has the AE900. I can't believe you are saying it is louder than that - wow.""

Depending upon how it is setup the AE900 can be pretty quiet or it can be fairly loud. In low power table top mode it is very quiet. Inverted it gets a bit louder, and louder yet in high power or high altitude modes. Also the DI in them makes noise and that seems to vary unit to unit.

So unless one knows how the AE900 is being run just comparing against it as a baseline is not very useful.

I am hoping the JVC is no louder then the AE900 in inverted mode.

ShawnFair point - not sure how he had his setup, but it was definitely inverted. I listened closely to my RS1 again last night. I'm wondering if the fan frequencies are somewhat different. Mine is very low - I think as the frequency gets higher, and the room amplifies it, you start getting problems. Just a thought.

I had a Runco 1100 for 6 years before I changed over to an RS1 last month. After living with the noise from the CRT for so long the RS1 sound is so low I have to look at the light to tell whether it is on when the picture is muted. That is not to say that other projectors are not even more quiet. It all depends what you are used to. For me, no problem at all.

I also have to look at my RS1's lens when I turn it on because I can't not hear it. It sits directly above and slightly forward of my sitting position. I designed my own "floating platform" that the RS1 sits on, kind of like a floating shelf, so I can't see nor hear it. I asks my guests last night if any of them could hear the PJ, no movie was playing, they could not hear it at all. YMMV.

So unless one knows how the AE900 is being run just comparing against it as a baseline is not very useful.

Agreed. Let me share my personal observations on this.

I had the AE900u mounted upside down on a ceiling mount. The fan/lamp were in the low/normal mode (forget now exactly what they were called, but it was the low fan setting). The AE900 fan speed would rise significantly when I shut down the unit to cool the lamp before the fan came to a stop. This is unlike the RS1 whose fan speed/noise do not go up when the unit is shut off.

The high fan mode in the AE900 was louder than the RS1 in its low mode (have not really tried the high altitude setting on the RS1). However in the normal fan setting, my AE900 was definitely quieter.

I am sitting *behind* the PJ. The AE900 was on a longer pole (to minimize the angle of the viewing cone on my HP screen) than the RS1 so it was actually closer to my ears. The exhaust from the fan was not an issue since the air was blowing out from the front and most of the noise from the AE900 was up front.

With the RS1, as others have pointed out its not the airflow from the fan per se which is the source of noise - it's also the case vibration (which you can feel if you put your hand on it). This adds to the overall noise level to an otherwise quiet room. I suspect that if the room is not specifically treated to control reflections, etc., and/or has a moderate noise floor the RS1 will not be noticeable and this may be the reason why there are differing views.

I first checked out the HD1 at ****************. Robert has a back room with the PJ and while its not a loud room as such, its not acoustically insulated from the outside showroom. In there the PJ was very quiet and I could not hear it. My first RS1 had a problem so when I got my replacement I first turned it on in my living room to test/check that it was working before I mounted it. In there it felt very quiet, but once I turned it on in the media room I thought that it was loud.



Finally, one could build a complete five sided cover, lined with sound absorbing foam, that would still be open on the front. This is a lot less effort than a sealed hush box with an optical glass window and additional fans.

It may even be sufficient to make a 4 sided box (rather than a 5 sided one) and leave the top open (assuming you are sitting below the PJ). That will control the sounds coming directly at you and if the ceiling is treated to control reflections, it may just do the trick -- and lessen the worries of cutting out air circulation.

I also have to look at my RS1's lens when I turn it on because I can't not hear it. It sits directly above and slightly forward of my sitting position. I designed my own "floating platform" that the RS1 sits on, kind of like a floating shelf, so I can't see nor hear it. I asks my guests last night if any of them could hear the PJ, no movie was playing, they could not hear it at all. YMMV.
Interesting! I wonder if the floating platform is the "barrier" that cuts the sound level ... if so, the solution may be simpler than what I'd been considering.

I also have to look at my RS1's lens when I turn it on because I can't not hear it. It sits directly above and slightly forward of my sitting position. I designed my own "floating platform" that the RS1 sits on, kind of like a floating shelf, so I can't see nor hear it. I asks my guests last night if any of them could hear the PJ, no movie was playing, they could not hear it at all. YMMV.

My RS-1 is completely silent for the first 5-10 seconds after I turn it on, then the fan starts. When I'm watching TV, that's usually after the receiver has come on, and the TV sound is audible drowning out the RS-1 fan for the most part. I can definately hear it when the sound is muted, I'm voting for unit to unit uniformity issues.

I also have to look at my RS1's lens when I turn it on because I can't not hear it. It sits directly above and slightly forward of my sitting position. I designed my own "floating platform" that the RS1 sits on, kind of like a floating shelf, so I can't see nor hear it. I asks my guests last night if any of them could hear the PJ, no movie was playing, they could not hear it at all. YMMV.

Could you describe in a little more detail the "floating platform"?

I wonder if this isn't, to some extent, a difference in people's hearing acuity. I have a friend who is my age and has normally functioning hearing. And yet, he can't hear something that's very obvious to me. He and I are 48.

I have a Prius and when I hit the brake I can hear the inverter do its re-generation thing. It's not THAT high (10kHz?) and fairly soft, but I can hear it over the radio. He can't even hear it with the radio off. Another friend (a woman) who is 40 can hear it plain as day.

I'm just wondering, as we get down to low dB sounds, how much does variation in hearing acuity plays a role in perceived differences.

Interesting! I wonder if the floating platform is the "barrier" that cuts the sound level ... if so, the solution may be simpler than what I'd been considering.
My HD1 is on an Auralex Gramma above my head :) and this doesn't seem to help much. I could try to put some rubber feet in between but my feeling is the noise comes from the projector itself.

Could you describe in a little more detail the "floating platform"?

My PJ is mounted in the basement so I used some very thin rods and suspended a 3/4" thick piece of wood that is about 2' x 1.5' is size. The upper ends of the rods are sitting on rubber dampening pads that absorb any vibration from the floor above, since the rods are attached to angle brackets that are attached to the joists. It also allows me to swap out PJs relatively fast since it is like they are sitting on a shelf that is suspended above my sitting position. I call it floating since it is suspended and with the added isolation dampeners between the rods and angle brackets it is like a "floating" platform.
It looks nice too!

My PJ is mounted in the basement so I used some very thin rods and suspended a 3/4" thick piece of wood that is about 2' x 1.5' is size. The upper ends of the rods are sitting on rubber dampening pads that absorb any vibration from the floor above, since the rods are attached to angle brackets that are attached to the joists. It also allows me to swap out PJs relatively fast since it is like they are sitting on a shelf that is suspended above my sitting position. I call it floating since it is suspended and with the added isolation dampeners between the rods and angle brackets it is like a "floating" platform.
It looks nice too!

Thanks,
What are you using for the rubber dampening pads and where did you get them?
Are the rods just all thread?

Thanks,
What are you using for the rubber dampening pads and where did you get them?
Are the rods just all thread?

I am using some round anti-skip pads (1" round x 1/2" thick) used for phonographs and these sit between the rod and angle bracket plate - kind of like a mini-shock absorber. They seem to work pretty well. I am using a 10-32 threaded rods that are 18" long and are now painted same color as the ceiling and shelf. Unless someone is skipping rope on the 1st floor, I don't see any vibration on the PJ. If the PJ is vibrating from the fan (I don't hear it if it is) I don't think it would transmit the sound anywhere else due to the dampeners. Also, about 8" above the PJ is my ceiling (of course) which is composed of acoustical tiles.

"The AE900 fan speed would rise significantly when I shut down the unit to cool the lamp before the fan came to a stop. "

Yes, and it was loud when it was running like that.

"However in the normal fan setting, my AE900 was definitely quieter."

OK, if the RS-1 is louder then normal/inverted on the AE900 sounds like I will want to explore quieting down the RS-1 too.

"With the RS1, as others have pointed out its not the airflow from the fan per se which is the source of noise - it's also the case vibration (which you can feel if you put your hand on it)."

That is good to know. Some damping on the case might help then. If it doesn't get too hot inside where it is vibrating maybe a coating or two of Loctite 'Color Guard' might help?

Thanks,

Shawn

I am using some round anti-skip pads (1" round x 1/2" thick) used for phonographs and these sit between the rod and angle bracket plate - kind of like a mini-shock absorber. They seem to work pretty well. I am using a 10-32 threaded rods that are 18" long and are now painted same color as the ceiling and shelf. Unless someone is skipping rope on the 1st floor, I don't see any vibration on the PJ. If the PJ is vibrating from the fan (I don't hear it if it is) I don't think it would transmit the sound anywhere else due to the dampeners. Also, about 8" above the PJ is my ceiling (of course) which is composed of acoustical tiles.

Thanks

OK. So I put some more thought into my DIY "shuttheheckup" box, and I wanted to get some feedback from you aeronautical engineers here. The fans are 120mm natch. The top is about 3.5" from the top of the projector to allow for the hottest air to rise above the unit itself and sit there until voided by the rear fans. The front intakes are angled for greater laminar flow, and I will likely be lining those structures and the rest of the box with some carpet padding and creating a properly curved (and acoustically absorptive surface) anyway.

I have no idea if this will cut the noise level down enough but one can only hope. I don't intend to use glass in front but I could try it I guess if I need more isolation. Conveniently enough the front opening is just big enough for a Prismasonic lens, but it won't be easy to move out of the way.

http://img147.imageshack.us/img147/5528/perspfrontdl1.th.png (http://img147.imageshack.us/my.php?image=perspfrontdl1.png)http://img147.imageshack.us/img147/4371/perspnotophb8.th.png (http://img147.imageshack.us/my.php?image=perspnotophb8.png)http://img247.imageshack.us/img247/9070/persprearqt0.th.png (http://img247.imageshack.us/my.php?image=persprearqt0.png)http://img522.imageshack.us/img522/8241/perspsiderx7.th.png (http://img522.imageshack.us/my.php?image=perspsiderx7.png)http://img522.imageshack.us/img522/1181/toprf2.th.png (http://img522.imageshack.us/my.php?image=toprf2.png)

I'm too cheap to buy a proper pre-fab box, but if one would be substantially better I could consider a recommendation.

a) Should the bottom piece follow the contour of the sides under where the lens is located? Otherwise will the bottom edge create a shadow along the lower edge of the screen?

b) Were you planning on leaving the top open?

Wildfire99: Your design looks reasonable. There is some obstruction to the inlet and outlet airflows, but using my hands, the flow rate seems low, so you may be fine. If you wanted a quick green light, you could carefully measure the outlet air temperature of the base RS-1 and then mock up your design using cardboard and check that temperature. As long as the outlet air is no warmer than baseline, you should be fine.
When I brought my unit back from the meeting with Tom Stites and put it on the shelf I project from, it seemed distinctly louder than when we did the A:B. I think the fact that it is near a 90 degree sheetrock corner is exacerbating things. My plan is a bit less aggressive than yours - I have ordered sound absorbing foam - (AcoustiPack Deluxe:
http://www.quietpcusa.com/acb/showdetl.cfm?&DID=8&Product_ID=48&CATID=6
My plan is a Baltic Birch board on the bottom that is secured by a pair of brackets to my wall. This board has sound absorbing foam on its upper surface, with hree thicker pads of sound absorbing foam on this board that will support the next BB board, which in turn has four posts that support the RS-1 via its leveling feet 2" above the board. This board will also have the thick sound absorbing foam everywhere (with holes for the leveling feet/posts). A four-sided cover (top, rear, and both sides; also BB) will drop over the RS-1, resting with foam side wall strips on the bottom shelf board. The cover is lined with sound absorbing foam. The front will be open, so the only fans are within the RS-1. A spring loaded button in the roof lets you push the on-off button, but the cover can also be simply lifted off (there are slots in the rear wall for the HDMI and AC cords). The RS-1 is essentially suspended on foam within but not touching the cover, and with the exception of the open front, this scheme ought to effectively suppress case vibrations. I'll post how well it works in a week or so.

Kevin

a) Should the bottom piece follow the contour of the sides under where the lens is located? Otherwise will the bottom edge create a shadow along the lower edge of the screen?
Hmm.. I hadn't thought about that. I suppose it should be cut out. I wanted to leave it there for an anamorphic lens but then I have no guarantee that the lens won't need to be lower anyway.

b) Were you planning on leaving the top open?
No. It will be covered, all surfaces lined with either carpet felt or 1.5" egg-crate foam. While fiberglass would be more efficient, it would also be more annoying. I could leave it open if need-be for heat but then I'd probably have noise bouncing off the ceiling if I didn't treat that too.

There is some obstruction to the inlet and outlet airflows, but using my hands, the flow rate seems low, so you may be fine.
It may not show in the pics but I specifically measured so that the wood does not obstruct the vent openings at all, though they do come close to the edges. If I have to I intend to trim down the felt/damping material to not obstruct either. I might have to hook up an IR repeater if the right-side duct obstructs the IR receiver on the PJ too much.

This seems like way too much effort for just some noise abatement, but ideally this will keep the volume down to a whisper, and I'll have a theater where silence on the movie means silence in the theater too.

This board will also have the thick sound absorbing foam everywhere (with holes for the leveling feet/posts).
Will that obstruct the underside intake for what I am guessing is the optical block's squirrel cage cooling fan?

I tried placing the RS-1 on a folded exercise foam mat for a couple minutes (about 6" thick) to try to damp vibration and it made no real difference. The core purpose of my overly complicated box design is to specifically absorb and divert the noise coming from the front of the PJ somewhere else other than the open room. It will be interesting to see how well that works, and if your solution will make it unnecessary. Keep us posted!

JVC is serious about continuous improvement, and some interesting models are in store, albeit not imminently

Any chance they could have something new, specifically a new flagship level projector by CEDIA? Essentially the unit that is going to take on the Sony Diamond, or better...

WF: The post height takes into account the thickness of the foam, preserving the space below the projector and optics block fan air access. My scheme founders if most of the noise comes out the front.

HN: Previous comments indicated that there will be a model below and above the RS-1. CEDIA is probably too soon.

Kevin

I'm surprised that everyone is only discussing the fan. What about the comment about light spill in the review. I didn't notice any light spill when I saw the RS1 (though it was on a black wall) nor have I ever heard anyone here mention light spill. So is there light spill?

I'm surprised that everyone is only discussing the fan. What about the comment about light spill in the review. I didn't notice any light spill when I saw the RS1 (though it was on a black wall) nor have I ever heard anyone here mention light spill. So is there light spill?
Yes, there is light spill. With the signal blanked, if I look into the lens of my RS1, I can see a bright green line that is at least partially responsible for considerable light spill around the screen. A totally black surround will obviously mitigate any spill problem but I can't help but think this is also hurting both the on/off contrast and ANSI contrast in low light scenes.

The light spill is, at least for me, nearly inconsequential. It's noticeable but only somewhat brighter than the actual picture area when display a full black field. It's not noticeable once the picture gets to any kind of realistic brightness, so I don't personally see how it can impact ANSI contrast in any meaningful way. It's about as much as an irritant as the bright corners, and those aren't very substantial either.

Good luck with your open hush box plan Kevin. As a second source for sound absorbing foam, i bought a bunch of foam from dB Engineering (www.800nonoise.com) for less than half the cost of that cited above. It is used by the Whisperflow guy who builds custom hush boxes. i built a box for my Sharp 20K because i'm easily distracted/annoyed by PJ noise during quiet passages. I vented mine into the basement ceiling with 2 silenx 120mm fans (the ceiling is partially open the adjacent shop) and i can just barely hear the PJ operating now. With the front of my box removed there is still significant snoise reduction, so hopefully your open front plan will provide adequate relief.

I haven't read this whole thread, so I don't know if the OP has determined that he has an abberant unit, but my RS1 sits right over my head, hanging down from an 8' ceiling. I have it in normal lamp mode to feed my 100" screen about 15' away.

At this distance, I can't hear the projector at all from a seated position. Even if I try to focus on the sound, it's hard to know if what I'm hearing is the projector or something else.

nevermind.

Jon V: Thanks; that looks like a great source. I probably overpaid. The Acoustipack material is shipping ground from California, so it will be another week before I find out how well it will work.

Kevin

I think it must really depend on where the projector is in relation to your head, and how sound bounces around in your room. Yesterday I turned the RS-1 on (in a room that had warmed up to 72, oddly enough) and it was distinctly quieter until I moved back into my seating position, which is in front and just below the projector.

I bet if you had the projector 8 feet away from the audience and at a 45 degree angle the audience with no nearby walls, it would probably sound pretty darn quiet.

Hushbox will also cut out your light spill some what. Anybody contact this guy yet? www.whisperflow.com

Were you subject to a minimum order size from dB Engg, Jon?

There was a minimum order size with dB Engineering but it was pretty small. i bought the 1/2" thick material and doubled it in a couple of places. it has an adhesive back, so it's easy to work with.
JV

Hushbox will also cut out your light spill some what. Anybody contact this guy yet? www.whisperflow.com

Too rich for my blood. Anything you have to get a quote for means you don't want to know how expensive it is, and the used Whisperflow prices are still above what I could build a box for (custom-purposed to boot).

Regarding RS1 air temperatures, last night I measured the delta between the inlet and outlet air temperatures of my RS1 and got a surprising large value of 63.4 F. This was using Normal lamp mode and after watching a 3 hour movie.

The RS1 is mounted behind the rear wall of my HT and sits upright on an open shelf with the front of the RS1 sitting 5 inches back from the wall. The two thermocouples were mounted 1/2 inch in front of and centered on the intake and exhaust ports of the RS1.

Just wondering if anyone else has taken these measurements ?

My "Acoustipack Deluxe" sound absorbing material shipped via UPS ground, and won't show up until tomorrow. I picked up some sheets of 1/4" baltic birch plywood with which to make the open-front hush cover. I may try a quick and dirty dry run using cardboard and the acoustic foam to see if building the cover is worth it - as much as I hope I am hearing case vibrations, the sound could just as easily be coming out of the front.

I got a little adventurous today and removed the upper lid and upper fan tunnel to check the exact model of fan and see how it is isolated (and if any compromise in isolation was evident). The fan is a Nidec D09E-12PM, a 12 VDC unit that draws 0.28A at 12 volts. Its data sheet is here:
http://www.nidec.co.jp/english/product/fm/pdf/p40.pdf
The data sheet is excellent, as it includes detailed charts of air flow versus back pressure. These are typically missing from the spec sheets of quiet fans for PCs. By the way, the fan is 38 mm thick; most quiet PC fans are 25 mm thick, which would imply poorer flow for a given back pressure and speed. The fan's nominal speed at 12 VDC is 2600 rpm, but I presumed that 12 volts is supplied from the RS-1 only when it is in high altitude and high lamp mode. Since I use it in normal lamp with the high altitude setting off, I checked the fan voltage in this mode, and measured 6.08 volts on the red lead relative to ground (the black lead). Since I put the lid back on, it occurred to me that it would have been worth checking the other modes; if one of them is an even 12 VDC, that raises the possibility of substituting a balanced, low-noise 12 VDC fan and running it in high lamp/altitude mode to give it the voltage it expects. One last item on the fan - it is a three wire device, and I had been led to believe that it has a fan speed output on the third (yellow) wire. I looked at this relative to ground with a scope, expecting to see a six volt square wave at two cycles per revolution. I didn't. There was the very slightest ripple on the third wire; I could have switched to AC coupling, cranked up the gain, and fiddled with the trigger level, but didn't bother - it took two hands to jigger the probes, and I was nervous enough about the procedure. Anyway, I don't think there is a fan speed signal. If anyone else knows that the typical speed signal is actually really low level, let me know.

The vibration isolation for the fan looks to be pretty well thought out. There are no fasteners used to mount the fan, which is smart, since these typically bypass any vibration isolation, routing fan energy directly into the case. There is a triangular rubber boot on each of the four corners of the fan, which feels llike it is made of pretty dead material. Its thickness is ~ 1 mm. Some fan plastic body features printed into the boot, so it may be compressed a bit. On the front and rear faces, the boots fit loosely within the injection molded fan tunnel. The boots are supported on the bottom by four small pads of ~ 3 mm thick, clear gummy material; two long strips of the same material contacted the top two boots. On the sides, at both the top and the bottom, are rectangles of ~ 2 mm thick black foam. All in all, the vibration isolation looks pretty good. If I pushed the fan to the side, I could get a louder case vibration. Lifting the fan out briefly didn't dramatically lower the overall noise level.

I brought a bit of Sorbothane vibration absorbing material in from work, and in the off chance that my shelf and/or brackets were transmitting any noise, did a two stage isolation - Sorbothane between the wall brackets and the first plywood shelf, and then three thick blocks of Sorbothane between that shelf and a second shelf that the RS-1 itself sits on. The Sorbothane is gummy enoiugh that bolts aren't required. Unfortunately, this didn't produce any noticeable improvement.

I'll post this week on the cardboard / Acoustipack dry run, and the baltic birch final version if the dry run seems promising.

Kevin

Sounds like the fan is well thought out and we need to look elsewhere for cutting the sound - maybe the box will help.

Following this thread closely!! :)

Kevin,

How about the noise from the two other fans? Does the Nidac contributes the most to the overall noise level?

I ordered a quit pc fan just to investigate the noise it's making and to check that the airflow would be on par with the flow coming from the exhaust port.
http://209.47.233.50/acb/showdetl.cfm?&DID=8&Product_ID=260&CATID=7

So far I compared with the Quitpc fan at 5volts and the airflow feels similar to the JVC's exhaust flow in low lamp mode. The Quitpc fan is very quit. My quess is it will be much quiter than the Nidac in the JVC. I will check again running it at 6 volt and see if that increases the airflow. ( I will need to make some kind of makeshift flow meter to do a good comparison. ) I'm not that worried about a given back pressure as the duct looks like it doesn't obstruct the airflow.

If I ever have the courage to replace the JVC's fan I think the QuitPC fan is up to it. To be safe I will run it in high alt mode to be safe. Since it's only 25 mm against 38mm there is also room to build the fan between to make shift mounting plates with addittional suspension in between to make up for the size difference and to get a better decoupling.
(I think my HD1 is a bit on the less quit side due to case vibration.)

It could also be that the other (radial) fans are causing most of the noise anyway. Replacing the Nidac isn't going to help much if that's the case.

"Anyway, I don't think there is a fan speed signal. If anyone else knows that the typical speed signal is actually really low level, let me know."

Maybe just a blocked rotor signal? If you open it up again watch that line and stop the fan or prevent it from spinning in the first place.

Shawn

OK, I just tried hushing up the RS-1. I failed. My $89.95 package of sound absorbing foam showed up yesterday. It's Acoustipack deluxe, from QuietPC USA, and is pretty impressive stuff.
http://www.quietpcusa.com/acb/showdetl.cfm?&DID=8&Product_ID=48&CATID=6
The foam has a heavy flexible layer at the back, and it feels very much like the lead blanket they drape over you when you get an X-ray. I had intended to do a cardboard mock-up before I built the actual baltic birch hush cover, but the cardboard is unnecessary - I was able to drape the three large sheets of sound absorbing foam over the RS-1, with one on each side, extending back to my rear wall and part way over the top, and another just for the top. The side sheets terminated at the lower of my two isolated shelves. The noise level was barely any lower than before. I tried one of the sheets below the RS-1, also imperceptable change. I then arched one over the front, with enough curve to not fully block the air flow. Even this didn't change the noise level much, which was surprising. This is all very disappointing - I sit two feet from the unit, and its drone is obvious, even during dialog. I had already (previously posted; #107) mechanically isolated the unit with a double shelf and Sorbothane.

I think that the reason for this is that the drone is dominated by low frequencies, which sound absorbing foam is not going to be helpful with. This even suggests that a full hushbox might be only provide limited attenuation. I am going to discuss this with colleagues today, and perhaps get a microphone and do a spectrum analysis of the sound.

Remaining options would be to look at changing the main fan, but as I mentioned in the fan posting (also #107), the sound didn't change much when I briefly lifted the main fan out of the case and set it on adjacent carpet. Perhaps it is the optics block squirrel cage fan - this would be a more serious intervention, probably more than I could consider. Frank Derks recently indicated that there were two more fans (total of three); I thought there were two. Is he right?

I love the projected image, but the noise level is a pain in the ass. Not sure what to do.

Oh, and before a volley of postings along the lines of "I saw one / own one, and it's inaudible; you must be a complainer" show up, note that the three seasoned reviewers of Home Theater magazine concluded that the RS-1 was "downright loud", and found this an objectionable aspect of the projector. It's not me, it's the RS-1, albeit there may be unit to unit variations.

Kevin

Kevin,

I would think that a full hush box would have to work (sealed with air ducts to another room).

Also, just a random thought, but do you have any test discs (video or audio only) that have a frequency sweep in them? SInce you already have the sound equipment at home, you might be able to play it and see if the JVC reacts to any particular frequency?

If so, that might give you some idea of what frequency is actually causing the vibrations. (Just in case I am not too clear in what I mean, for example, if a car drives down the street thumping low bass, and it shakes all the windows and objects in your house, you can also get high frequency noise, even though the source of the noise is low frequency???)

Best Regards,
Doug

Doug: An excitory sweep is one way to elicit resonances in a structure, but in this case, where the RS-1 is a noise source, it would be better to either mike it and take an FFT of the output sound, or put a piezo accelerometer on the case and do the same. I will probably do one or both, and will report back, although it may take a week or so.

Kevin

Kevin, I used acoustiblok (http://www.acoustiblok.com/products.html) successfully in my room to block bass frequencies. Not sure if they can be had in small quantities though. :(

Incidently, what material did you use for the surrounding box? Would the use of a denser material such as 3/4" mdf have helped? I'm wondering if the problem you face is that the foam is useless and the material used for the box is itself resonating?

Sankar: As mentioned in my post, there was no rigid cover - I simply draped the foam over the RS-1.

Kevin

Sankar: As mentioned in my post, there was no rigid cover - I simply draped the foam over the RS-1.

Kevin

Aah! I missed that one ...

First the radial fan next to the lens assembly
I suspect this cools the 'outer' optics and the lcos chip backplanes.
(One of the lcos chip assemblies is visible through the lens hole)

http://www.cine4home.com/reviews/projectors/JVC-HD1/Bild6b.jpg

Second the Nidac:

http://www.cine4home.com/reviews/projectors/JVC-HD1/Bild13.jpg

This fan removes the hot air from the entire casing.

And third:

http://www.cine4home.com/reviews/projectors/JVC-HD1/Bild15.jpg

This looks like a smaller radial fan that blows air directly to the lamps heat spot.
It's mounted behind the metal plate visible left of the yellow arrow.


Also I suspect another fan that's not visible in any of the pictures.
From the pictures I can't line up the visible fans (1 to 3) with the removable filter.
I suspect that the filtered airflow is used to cool the 'inner' optics.

Frank: Thanks. In your third picture, my visual memory from my peek inside was that this was some sort of thermal sensor, not a fan (but I could be wrong). While there could be a third filter fan, I had been thinking that the filtered air was routed to the squirrel cage fan (again, speculation - I did not trace out the air flow). So there could still be only two fans.

Given that the main fan is a 2600 rpm device, operating at half voltage, that should put its speed around 1300 rpm, or ~ 22 Hz. This is quite low, so I suspect we are either hearing harmonics of it, or the squirrel cage fan. I could check the actual rpm on the main fan with a variety of methods, and this plus a spectral analysis of the acoustic output would be helpful in resolving which fan is the primary culprit. For that matter, with the lamp exposed, (very) briefly stopping the fan would show how loud the squirrel cage was.

Kevin

No I didn't mean the metal round object at the point of the arrow. (That's indeed the thermal sensor)

I mean the one behind the metal plate just before the bend in the air duct about one inch left of the yellow arrow.
It seems to blow air just across the front of the lamp.
The location of that fans exhaust line up with the wire grid at the lamps sides:

http://www.cine4home.com/reviews/projectors/JVC-HD1/Bild18.jpg

This looks like a smaller squirrel fan.

From another angle the beforementioned metal plate is on the left:

http://www.cine4home.com/reviews/projectors/JVC-HD1/Bild14.jpg

Doug: An excitory sweep is one way to elicit resonances in a structure, but in this case, where the RS-1 is a noise source, it would be better to either mike it and take an FFT of the output sound, or put a piezo accelerometer on the case and do the same. I will probably do one or both, and will report back, although it may take a week or so.

Kevin

OK,

I just remember you saying that you thought the noise might be coming from the entire case. That, combined with your assesment that the noise was very low, made me wonder if there was one source of the motion, which excited another source of the noise.

Just a thought, though.

That air circulation does kind of look like the bass tubes that Bose is so proud of. I also wonder if it is a frequency that sets up as a standing wave in the tube?

When troubleshooting, I sometimes check low probability solutions, if they may be very easy to check, and the others not so easy. Of course if you don't happen to have a frequency sweep at home, that kind of blows that reasoning out of the water.

Good Luck.

Best Regards,
Doug

I spoke today to a colleague at work who is far more knowledgeable about acoustics than I. He said that all of the acoustic dampening foams he has seen have attenuations that roll off big time below 1 kHz. The fan primary speed on normal lamp is ~22 Hz, but this frequency is both near the edge of audibility, and the small size of the fan makes its acoustic coupling for this frequency very low (the wavelength is many times the size of the fan). The expected range of fan acoustic output, from a size/coupling perspective, higher harmonics due to non-linear turbulent flow, and the seven fan blades and four spokes, is in the 100 - 200 Hz range. This is easily audible, correlates with the low drone I hear, and is in a range where acoustic foam is nearly useless (as I observed).

His best suggestion for suppressing the noise, other than a different fan (and I have yet to check by briefly stopping fan motion if the lamp or optics fan is the biggest noise culprit), was to "throw mass at it". Basically, building a stiff, heavy box, with no attempt at foam lining, is the way to shut the projector up. Unfortunately, this would also entail venting the hot air out, an optical window, and it would be big and heavy. I asked about 3/4" plywood. He suggested masonry or steel. Yikes. I may simply have to try to ignore the drone. Not a lot of options at this point, although I will try and determine which fan is the offender. If it were the lamp fan and a really well balanced alternative was available that could match the flow at the design's back pressure, that is a possibility. The squirrel cage fan, since it moves filtered air and cools the tricky bits, is not something you would want to mess with. Squirrel cage blowers are much better at moving air when there is higher back pressure, such as a filter and crowded microdisplay section would impose. They have a lot of blades, and this could easily be the main noise source. It is not elegantly isolated like the lamp fan, but is rather directly connected.

Running out of options... Still, a georgeous image!

Kevin

Something that worked well to dampen projector noise for me on a different projector was using rigid fiberglass to build a 4 or 5 sided box with the open side(s) opposite the sweet spot seats. This noticeably reduced the fan noise at the main seating area without having to build a sealed hush box with powered vents. It's cheap, it's easy, it's lightweight ( relatively ), it's quick. I can't say it's pretty - but you might try it. If it makes a noticeable difference in noise level, you can make it pretty.

There are so many quiet fans out there, have you contacted Silent PC: 360-882-1883, they have an abundance of quiet fans from 120mm and all sizes.... I use the nexus and many other fans which are designed to be low noise. You should be able to match the Flow rates with less noise....

It peeves me when we spend a lot of money on this stuff and they skimp on these parts. Its just like the $8,000.00/pair speakers that have crappy crossover components....

Something that worked well to dampen projector noise for me on a different projector was using rigid fiberglass to build a 4 or 5 sided box with the open side(s) opposite the sweet spot seats. This noticeably reduced the fan noise at the main seating area without having to build a sealed hush box with powered vents. It's cheap, it's easy, it's lightweight ( relatively ), it's quick. I can't say it's pretty - but you might try it. If it makes a noticeable difference in noise level, you can make it pretty.

I was thinking of something similar --- using 3/4" mdf and lining it with 1/4" rubber which is not stuck to the bottom, but stretched loosely on 1/4" spacers (so there is an air gap between the rubber sheet and the MDF). This will hopefully help in absorbing some of the sound energy and damp the level sufficiently for those closest to the PJ.

Just wanted to see if there were any updates from the last 10 days?

jcg

Personally, I put my RS-1 up on a shelf higher and further away from the seating area than it was, and the noise was not impacted to any noticeable point. However one thing that did abate the noise, interestingly enough, was the PS3. Since the 1.8 update it runs the fan pretty high when playing SD-DVD, and it effectively matches the RS-1 and since it's higher pitched kind of neutralizes it. Since it's noticeably better at the job than the A2, it gets left on most of the time. I can definately see how someone with a few fans in the room would say the RS-1 is silent... it's really about the noise floor of the room.

I did try to isolate the shelf the PJ is on, with no useful result. The vibrating chassis seems remarkably effective at exciting whatever it's sitting on or near. It really will need to be wrapped up in a box, possibly even sealed with glass in front. I'm still way more interested in watching movies than building boxes though... so the fan isn't supremely awful in any way.

The different noise levels being experienced appear to be, as demonstrated here last night, the result of differences between RS-1's. We measured three RS-1's last evening and all had different measurements. The low at one foot was 42 dB and the high was 53 dB, so differences do exist between units. I think Kevin McC. makes a solid argument for the likely cause of varying noise levels.

In all three cases, the owners here were satisfied with these levels.

Jim

Which weighting did you use? Manufacturers use A weighting for reported levels. Your levels, 42 DB and 53 dB at one foot, translate to 32 DB and 43 dB at 1 meter, which is the standard distance for reporting sound levels. The former is a noisy, but tolerably noisy projector, and the latter is intolerably noisy. Couple with the acceptance of both units by thir owners, multiply by pride of ownership, and you can explain why there is so much controversy about the noise from these projectors. Two things are clear: The projector generates significant noise when it runs, and JVC has a quality problem with that. It isn't hard to believe that the fans have a quality problem, since I have run into that repeatedly, but it is hard to understand why JVC would put one of those fans into their new product, at this price point. On the other hand, given the demand for this pj, there is considerable pressure to ship product, and if the fan vendor decides to salt the shipment with poor quality, you have this issue. Owners have a responsibilty to force JVC to make good on this problem. Those with noisy pjs must report the problem, and insist it be repaired.

have you a soluce to diminue the noise levels ?
can i have the reference and picture to this fan (replaced) in the rs1/hd1?
thank you for your return

Wow this rally grabs me, I heard both the prototype and the one I now own. Neither one was really that loud the only time I could hear it was either High mod or High Altitude mode. Even then they were now that loud, I hardly hear mine. I wonder if there is more than one source for the fans or something.

So did anyone ever experiment with any of the ideas discussed in this thread? The thread was active and then just died and I'm sure there are others out there wondering if anything can be done to make the projector quieter.

jcg

I'm just living with it. It's not the end of the world. Truth be told, I think it gets quieter the longer it's on, esp. after a couple hours. Either that or the PS3 gets louder.

With the summer starting to hit in force I end up having auxiliary pedestal fans from Wal-Mart for air circulation in the theater now, which are about 4 times louder than the PJ anyhow.

Come fall if I end up redoing the theater I might send it in during the downtime, since it has some annoying non-linear misconvergence (2 pixels red) on one edge, but I haven't played with lens shift to try to fix it. It's another one of those things that is just so irrelevant while watching a movie that I don't want to mess with it. (Last night was Hellboy on BD... that's a fantastic looking film, too bad shadow detail and contrast were spotty.)

I have concluded that my options boil down to two: either put up with an audible projector during quiet scenes and low level dialog, or build a stiff walled box around the projector, with a glass window and much quieter fans to move air through the box. The RS-1 is big to begin with, and the size and visual impact of an enclosing rectangular box tempers my interest in this solution. Despite initially being convinced from user comments that the issue is mostly unit to unit variation in audible noise, an A:B with Tom Stites of JVC and his observations suggest that it may be more a case of room acoustical characteristics, personal thresholds, and additional ambient noise sources, along with perhaps some unit to unit variation.

A good movie pulls you in where you forget about the constant low drone, so we may just leave it as is. Less than ideal, but certainly practical.

Kevin

I have concluded that my options boil down to two: either put up with an audible projector during quiet scenes and low level dialog, or build a stiff walled box around the projector, with a glass window and much quieter fans to move air through the box. The RS-1 is big to begin with, and the size and visual impact of an enclosing rectangular box tempers my interest in this solution. Despite initially being convinced from user comments that the issue is mostly unit to unit variation in audible noise, an A:B with Tom Stites of JVC and his observations suggest that it may be more a case of room acoustical characteristics, personal thresholds, and additional ambient noise sources, along with perhaps some unit to unit variation.

A good movie pulls you in where you forget about the constant low drone, so we may just leave it as is. Less than ideal, but certainly practical.

Kevin

My sentiments exactly. I fashioned a box using cardboard, painted the outside black and temporarily fitted it over the projector to get a sense of what the completed box would look like ... yuk!! It was a huge black box that demolished the look of the room! I can still hear the PJ, but with the passage of time seem to be less bothered by it. Furthermore, I've now put a fan in the room since summer is upon us and that has overwhelmed the RS1.

You know, I have been making a point to see other 1080p projectors in use in owners theaters.

My HC5000 and the RS1 I got to see are two very unforgiving projectors with legacy sources like Laserdisc. I have to give this particular point to the Pearl hands down. I think you give up some ultimate sharpness on the best sources, but Laserdisc looked very good at 110" on a Pearl. I am milling over changing projectors these days.

My LD collection is still way way important to me and I find myself not using them as much with my HC5000 as I did with my old 720p projector. I have an ae1000 on the way as well to test.

Just another comment by "me" the "peanut gallery" on 1080p shoot outs aside from the loudness of fans and what not.

Heck, my AC unit trumpts all projectors and source devices ever built I am sure of it. :)

Opinion dismissed, my RS1 is whisper quiet - I would say my PS3 is 2-3X as loud, the 360 about 2X as loud...non-issue if mounted 2 feet or more away from listeners.

ELmO

Opinion dismissed, my RS1 is whisper quiet - I would say my PS3 is 2-3X as loud, the 360 about 2X as loud...non-issue if mounted 2 feet or more away from listeners.

ELmO

I'd say the RS1 is about as loud as the PS3, maybe a tiny bit louder... Even so, neither one of them bother me.

The RS1 cooldown versus Panny AE700....The RS1 is quieter and faster...

I'd say my PS3 is faulty then, it's an airplane.

I love the RS1.

-ELmO

Opinion dismissed, my RS1 is whisper quiet - I would say my PS3 is 2-3X as loud, the 360 about 2X as loud...non-issue if mounted 2 feet or more away from listeners.

ELmO

Good to hear that. It appears that there is some variability in the noise levels of RS1's. Mine is not whisper quiet (wish it were) ... its 3 feet above and a couple forward and yet noticeable in my room. I find that it is a tad louder than the Panny AE900u that it replaced.

And yes, it is in the low mode etc. :)

Another data point from a new RS1 delivered yesterday. Inaudible 2 feet above and 2 feet behind with no audio or anything else making noise. Must be a bad unit or someone with Steve Austin ears tuned for that frequency. I imagine someone screaming at the mice in the walls for breathing too loud.

I don't want to sound "rude" but over the past couple of months or so, the following points have been discussed about the RS1 (here and in other threads)

There are unit to unit variances. Earlier in this thread someone measured a 11db difference between units. We may agree or disagree with these measurements and the magnitude of differences reported, but it does suggest that some units are louder than others.
The "noise" seems to be generated by a vibration of the case -- and may not be from the fan bearings.
The level of ambient noise in the room has a significant impact on whether or not the PJ can be heard. Acoustically treated media rooms tend to be rather revealing.


The fact is that some people do indeed find their units to be loud and many don't. This may have something to do with the hearing abilities of the owner or of his/her tolerance. But surely it is also possible that these differences are real and that some units are louder without being classifiable as "defective"? :D

If you have a near silent unit, you are one of the many lucky ones. It does not mean that nobody should be trying to find ways to control the noise that they (as one of the less fortunate ones) are sensing! :)

This thread has some very useful posts about silencing the unit for those who are unlucky to have the noisier ones coupled with acoustically revealing environments. I for one have been tracking this thread to see if someone comes up with innovative solutions. Reading multiple posts that say "my unit is silent" does teach me that there are many quiet units out there ... but it neither convinces me that I have a deathly silent unit nor does it tell me how to find ways to control the sound.

This is similar to the rainbow induced headaches that some have reported with dlp projectors ... knowing that 99 out of 100 people are not bothered doesn't cure that one poor bloke of his headache - even if ALL 99 tell him repeatedly that they are not bothered! ;)

If we wish to start a thread about who finds their units loud and who does not, let's do that separately. We could even make it a poll to help those who are considering the RS1 but have questions about how likely it is that they would get a "loud" unit. In that thread one group can opine about how the other group is "deaf" or filled with "super-human ultrasonic ears". :D

Another data point from a new RS1 delivered yesterday. Inaudible 2 feet above and 2 feet behind with no audio or anything else making noise. Must be a bad unit or someone with Steve Austin ears tuned for that frequency. I imagine someone screaming at the mice in the walls for breathing too loud.

MICE IN THE WALLS!?!?!?!?!

WHY DON'T THEY COME OUT AND ENJOY THE RS1 SHOW? :o

MICE IN THE WALLS!?!?!?!?!

WHY DON'T THEY COME OUT AND ENJOY THE RS1 SHOW? :o

LOL!!! :D :D
Maybe it should be "Mice on the walls!" :)