NEC XG fan mod discussion and my mod!! - Page 2

Gary,
Just a minor correction. I had 132 after 40 minutes. Doug

Gary I didn't get a chance to use my XG, but I found this from a mate, Chris S:

"I thought this would be something that may interest you.

I got my Lian -Li and have installed it into my HTPC bay, but I've extended the cable runs to the probes to 5mts leading into the hushbox.

The extra cable length made no difference to temp readings which I checked before hand.

I have one probe under the middle STK screw of the C-drive, another in the same place but on the F-drive and the third one on the green neck board heat sink.

These are the readings I get after 2 hours use with aggressive raster usage in a sealed hushbox.

C-Drive-43-44 degrees

F-Drive-43-44 degrees

Green - 42 degrees

I remember the base temps for the XG being around 50-55 degrees, so I'm pretty happy with the results.

Chris.."

Oh, I should add this was an XG-750, so it may be a little different, but the neck board and C drive temps are identical to mine.

Mark

Has anybody tried some of all of Gary's fan mods on their XG? I'm thinking of trying some of them to mellow out the noise on mine.

What 92mm Arctic fans did you use for under the CRT's? They have 2 different styles that are close in sound level and CFM. One has a kind of an open back that I think is for exhaust purposes only but a little better specs. And another type that looks like a normal case fan. I'd like to order these up and give it a try but would like someones guidance on which ones to get

Take a look at these fans at Newark : http://www.newark.com/NewarkWebComme...KU=31K9983&N=0. These are 80X25mm Panaflo's that have a locked rotor output so you won't lose your dead fan warning and should be much easier to mount than the 92mm Artic's also they have more airflow at a lower rpm than the stock 80X15mm fans. Stock; 31 cfm @ 3100rpm @34 dba @ 12V, FBA08A12M1BS Panaflo 32 cfm @ 2450 rpm @ 28 dba @12v. One thing you need to consider is the neck fans are running at 8 volts on a stock NEC, at this voltage the stock neck fans are just barely audible but the replacement is dead silent(approx 21 dba) . By far the biggest noisemakers are the case side fans, these are the same 80x15 high speed Panaflo's that are used on the CRT necks but they are running @ 10v. The replacements should work good here also. I have 5 temp probes in my ceiling mounted XG135LC and plan to post the results later this week as I am installing these tomorrow.

ScottH1, Thanks for the info. Please post your results so we can all benefit! The side fans are definitly nasty loud and easy to replace. Also the small 60mm ones should be easy. I'm noodling the idea of trying the silenx here. I'm concerned though. The 60mm ones in my projector aren't the same as what Gary found. The ones in mine are Sanyo and rated at 18CFM. The fastest Silenx barely makes that and that could be over rated also. It seems Gary was able to get by with the med speed ones with his projector though?.?

Great posts guys. I just got a XG-85 and removed one side fan last night to play with it on a variable power supply. I too found the blade design very whiny even slowing it down lower then the 10 volts it normally gets, it's still noisy, buzzy, whiny! yuk!
I modded my Sony 1252 and got it very quiet, no hush box needed but the NEC starts off more noisy and has more fans in more hard to reach spots compared to the 1252 and also seems to run hotter.
So it's a project, but thanks for the help on here now it will be less of a project.

From where can we download the XG service manuals? It seems they are not on Curt's site. I wouldn't want to attempt to disassemble my set without one.

Ok I've started digging into the fan project.... Anybody know the easiest way to get at the 3 fans above the CRT's (without pulling the tubes)? I thought I had a solid plan after seeing that picture of the assembly removed to mod the fans on that German website. After looking into it I don't see an easy way to get that assembly out without pulling the tubes.

I changed the 3 small 60mm fans tonight. Running the silenx compared to the stock ones on the bench it's huge difference, but overall once in the projector there's still a lot of work to be done.

Hopefully I'll have time to swap the side fans tomorrow. This will require a good amount of modifications. I'll either have to trim the plastic case to allow them to fit. Or cut modify the metal chassis. I'll probably just cut out the fan area in the plastic case. I've painted my case black so the fans should blend fairly well when it's all done.

Lastly, if I can figure out an easy way to get at the CRT fans I'll go after them. I think this will be necessary to realize a good overall sound reduction. I've run a test on a parts machine here with no fans but the 3 crt fans running. They still produce a good amount of sound just by themselves.

Once I get this all done I'll try to snap some pics to hopefully help some others. One thing for sure on the 60mm small fans. Get the high power ones if you go with silenx. The beginnig of this thread mentions the medium power ones. This is only subjective but even though they are rated essentially the same as the stock fans for CFM, on the bench placing my hand over the output, I'd say the stock fans have more CFM than the Silenx. It'll be interesting to see how this part pans out.

One other thing.. I've seen mentioned in multiple posts that there's a fan in the front of the case under the lense? I don't have or can't find this fan in either of my machines. Both are early XG 75 and 135 machines that are non LC. Was this fan added in the later machines or only in the LC machines? Or am I just blind?

Thanks again

Only LC have another fan between the lenses - you wouldn't miss it, it's right on top.

And you cannot get the Def coil fans without pulling the tubes.


Anyone taking pics of their mods? But a Hushbox is probably safer and more effective.

Mark,

Any suggestions on least amount of pain to pull tubes? Service manual wants you to pull the top hinged assembly then remove top brace across tubes then lift entire assembly out. Is there a way to pull them out the front so I wouldn't have to disconnect everything? I guess I don't mind pulling the tubes as long as I can figure out a way to do them with least amount of dissasembly. One thing is for certain that those fans need to be changed to realize a nice improment in sound level. The ones on mine are really loud.

Also what's chance of doing this while ceiling mounted? I know it's going to be light years more difficult but possible?

Ok I figured out how to get them out while on the ceiling. I didn't have to pull the tubes but I did have to do some carefully planned moves lowering the whole tube assembly a few inches.

Having a parts machine around really helps. I was able to test my whole plan and figured out exactly what needs to be removed and what doesn't..

I've got the 3 fans out now. Hopefully I'll be able to replace before tonight's over and see if my sound level has improved

well it's back together. much quieter now..... not silent but much better. no fan whine anymore just air movement.

one thing brings another though.. now I've got a "swim" in my picture on red and blue. blue swims fast (vertical wavyness in test pattern) and red swims slow. you have to look for it in a picture but it's obvious in a test pattern. I'm pretty certain its vibration induced from the crt fans. by cutting the power to the blue fan the blue stabled up. Well on to figuring out a solution to this one.

Getting the tube assembly back up into place while ceiling mounted was quite the job. NEVER AGAIN! That took all night to get eveything back correctly. I could probably do it faster now but it sucked.

Talking to Gary he said he was able to get at those fans with nothing but a small screwdriver and removing the powersupply. Didn't look feasable to me at the time so I lowered the tube assembly about 2 inches and then slid the fan bracket(lower tube mount) out..

Ah well the saga continues. on to fixing the swim.... and pray for reliability... oh still need to modify the side casing to allow for the thicker fans.

check the temps on all critical components. You have changed the airflow characteristics in the PJ by changing the fans. Some critical components may no longer get sufficient cooling.

I'd guess it's more likely a magnetic effect than mechanical vibration. Those tubes are in there pretty firmly. But if your fan generates a rotating magnetic field, that could cause the picture to shimmy. I'd expect the red and blue to do it at the same speed, though...??

Gary, good thinking and probably correct. Didn't even think of that but I was pretty spent when I got to that point last night. I'll try to look into it some more this weekend. I think theres a little bit of room in there to try and bend the fan bracket down away from the tubes. Maybe a cm or 2 will get it done.

kschmit, There really shouldn't be too much changed... All I did was swap one for one on the fans with equal or slightly higher CFM. The only thing I have too much concern over is the 60mm fan on def tunnel and 2 of them in the powersupply. Even though I got the high power ones they are the only fans that I question their output compared to the original fans. I'll definitly keep a keen eye to the temps though while I shake out the rest of this project.

One of the Aussie guys stuck a bathroom/kitchen ceiling fan right above his XG - caused CHAOS.

The rotating magnetic field will screw everything. I have a green neckboard fan which does the same thing.

So it's probably the fans...ouch.

BUT, there is a possibility it's something else. See if raising and lowering contrast slowing makes the shimmer change/stop.

Mark

Any good ideas for solutions to the magnetic interference? I tried to bend them away a little bit best I could do without tearing it apart but no improvment. So I'm thinking most likely have to change fan types for this spot? Obviously can't shield a fan in any way.

Here's an interesting article starting on page 4 that gives some insight into the internal construction of a cooling fan. I think it's clear from this that there's not necessarily only a single design and principle of operation for fans, but that there's plenty of opportunity for stray magnetic fields to get out as the fan rotates. Maybe we need to know how the original ones work, and then find equivalents?

http://www.emcw.org/images/EMCW%20News.pdf

Also see

http://www.peswiki.com/index.php/Electric_motor

Carp
Thanks for the links and trip down memory lane. Yeah that all brings back the days when I was getting my EE. Thankfully I've been doing mostly radio stuff since school and not much of any motor/electric machines work.

Well I had a chance to look at this again while I was fresh, well slept, and not after a long days work.

Long story short... I've got it resolved!

Looking at what I had, it was quite obvious why I was having wavyness issues. The way I had the fans mounted they were above the bracket closer to the tube necks. If you could look at it from the side you would see that the fan was actual behind the bell of the tube. I pulled it all apart again and moved the fans to the other side of the bracket. so they are now closer to the bottom of the projector and more important the entire fan is physically above the entire tube and not slightly behind it. The only trick of the deal was ensuring correct placment and also maintaing good clearance behind the powersupply where there are 2 other fans right there. That took 2 attempts to get right. Well it's all done and together. No wavy lines! Only thing left is to cut out the side case panels where the new fans will stick through then put it all back together.

Off to watch some tv and movies

Oh and although I've gotten really good and dropping the whole tube assembly - NO MORE LAST TIME!

Although the XG is my favorite pj, it's cooling is the least efficient of all that I have modified, the Marquee was well thought out and easy to mod, the Ampro's are easiest of all...but as you guys see the XG is a mess...when hanging on the ceiling, the three exterior fans that blow outward work against the laws of physics!!!
If your XG is on the ceiling, the laws of physics tell you that hot air raises, yet in the factory position, those fans are trying to pull air down away from all the heat sinks mounted at the top of the pj. (I've been through, and documented all these temp measurements all some length in here a year or two ago...all our stock readings look about the same)
First thing I did was turn all the exterior fans around, so they blow into the chassis, and create more air to flow up through the drive board heatsinks. (remember this is for XG's mounted on the ceiling)
However, for my setup, I don't need to change the fans because my H-box is somewhat more "enclosed" than the average...my lenses are sealed, and the cooling air must flow through a acoustically treat 3 ft tunnel, so very little sound gets out of the box.
I have been able to drop the temps on my crt amp/ drive boards an average of 25 degrees F with a single fan, mounted in my attic that pulls through all the chassis openings in the top of the pj...I simply used 1/2" styrofoam and built a seal around the top of the pj to the ceiling...the attic fan then pulls air through the whole top of the pj, and man does it cool!!!
To start the fan I simply installed a 12 vdc relay (controlling 120 to the fan) and ran the relay's control wire to the fan connector vacated by the fan I removed up on the lenses. (why is that fan up on the lenses?, it doesn't do a thing) it's a 15vdc output so you can add a resistor to drop the volt, but I have found that I don't need it, the relay has worked fine over the last year. (I also have an alarm light on the bottom of my H-box, so if the fan quites working I get a red light.
Anyway just another way to cool the XG, and this one keeps it from heating up your HT room.

Wow... and here I was thinking it a matter of simply replacing fans (like in a PC)....

I've read through much in this topic, but perhaps somebody can quickly sum things up... my projector (XG 110LC) just arrived so I would like to make any fan modifications before I attach it to the ceiling.

* Does the projector somehow sense the RPM of the fan, and act up when it's not 'default'?
* Can one basically use any kind of identical size, but lower dB spec, fan, or should specific things be kept in mind?
* Are specs labeled on the standard fans? So I know voltage.

I haven't dug into the pj that deep yet, so I haven't actually seen any fans yet... I'm not sure mine has the same (amount of) fans as the one Gary described?

Basically, should I really dare?

I'm quite well familiar with pc's, have poked about in an old BARCO and I know the basics of electronics and have some proper soldering/measuring equipment. Does that suffice? Combined with common sense...

Having been to the top of the mountain and back... I'd say leave well enough alone. It's quieter but definitly not silent. The risk to reward ratio on messing something up trying to get at some of the fans isn't there.

Regardless if you want it really quiet you have to use a hushbox anyway. That being the case I'd do some digging on what KennyG did a while back.

In my case the hushbox isn't practical (I've got low ceiling clearance) and a plenum with ducting not possible either. So I took the high road to bring something from aweful to tolerable. It's odd though that all the fans I put in there are pretty much silent on their own but all together still make some decent racket.

Honestly, if I didn't have a more or less complete backup machine here (with burnt tubes) I wouldn't have done this. Even though I supposedly have equivalent air flow long term reliability remains to be seen. And I'm going to have to butcher the side case to fit the new fans.

I think zman is right. You could replace all the fans (a HUGE job) with absolutely silent 0dB fans, and you would still get a significant amount of noise from the turbulence of the airflow. Since you won't find 0dB fans, you can add fan noise onto that. You can definitely reduce the noise, but you won't get rid of it. You really need a hushbox if at all possible.

Well, that's not exactly the answers I was hoping for, but I'll let you guys get away with it

No idea how to manufacture a hushbox... and if I did, I doubt it'd make the lady happy.... it'll be ceiling mounted by the way.

I guess I'll have to turn the amp up a couple of notches