AVS › AVS Forum › Audio › Subwoofers, Bass, and Transducers › Official Rythmik Audio Subwoofer thread
New Posts  All Forums:Forum Nav:

Official Rythmik Audio Subwoofer thread - Page 237

post #7081 of 9696
9/20/12 at 7:06pm
Quote:
Originally Posted by cwunker View Post

HI Larry,
I have been up in the air about whether to get a sealed or ported. What has been your impression of the differences? I apologize if you have already discussed this in a previous post but I don't recall seeing the post.
Chris

Chris
I wrote this some time back and never posted it but because you asked I’ll post it now.
Now that I have heard both the F15 and a FV15, well not really a true F15, I have a DS1505 that I switched from sealed to ported. My sealed enclosure was a little larger than the F15 which I’m told makes it play a little lower, but the ported is the exact dimensions of the FV15. The reason I did this is I never thought the sealed blended well with my other speakers. I have all Klipsch Synergy speakers with the mains being the big ported F3’s. They have been described as harsh and in your face and to a certain degree this is true. I would describe the sealed sub as being very smooth and mellow that doesn’t mean that it won’t get loud, I could turn up the gain and over power the F3’s that have a sensitivity rating of 97db, but it just didn’t blend right with them. So I talked to Brian and he told me how to convert the sealed to ported, as most of you know he was very helpful. I would describe the ported as more powerful and fuller and it matches and blends much better with my F3’s. So when you are deciding on sealed vs ported and 12 inch vs 15 inch your room side does matter but more important than room size is what speakers are you mating the sub to and how they will blend with each other. It’s not all about output the sound signature of the sub must match the rest of your system for it to sound its best. As you can see from the graph that as for as output goes there’s really not a night and day difference, by about 37Hz up they are the same. But there is a difference in the way they sound so you can’t tell everything from the numbers alone. Sorry but I don’t know what the extension filters were set on for these measurements they were taken months apart but from the same listening position, if I had to quess I would say the sealed was 20hz mid and the ported 14hz low but that is a quess.

Reply
Reply

AVS Top Picks

post #7082 of 9696
9/20/12 at 7:45pm
Quote:
Originally Posted by LarryU View Post

Chris
I wrote this some time back and never posted it but because you asked I’ll post it now.
Now that I have heard both the F15 and a FV15, well not really a true F15, I have a DS1505 that I switched from sealed to ported. My sealed enclosure was a little larger than the F15 which I’m told makes it play a little lower, but the ported is the exact dimensions of the FV15. The reason I did this is I never thought the sealed blended well with my other speakers. I have all Klipsch Synergy speakers with the mains being the big ported F3’s. They have been described as harsh and in your face and to a certain degree this is true. I would describe the sealed sub as being very smooth and mellow that doesn’t mean that it won’t get loud, I could turn up the gain and over power the F3’s that have a sensitivity rating of 97db, but it just didn’t blend right with them. So I talked to Brian and he told me how to convert the sealed to ported, as most of you know he was very helpful. I would describe the ported as more powerful and fuller and it matches and blends much better with my F3’s. So when you are deciding on sealed vs ported and 12 inch vs 15 inch your room side does matter but more important than room size is what speakers are you mating the sub to and how they will blend with each other. It’s not all about output the sound signature of the sub must match the rest of your system for it to sound its best. As you can see from the graph that as for as output goes there’s really not a night and day difference, by about 37Hz up they are the same. But there is a difference in the way they sound so you can’t tell everything from the numbers alone. Sorry but I don’t know what the extension filters were set on for these measurements they were taken months apart but from the same listening position, if I had to quess I would say the sealed was 20hz mid and the ported 14hz low but that is a quess.


Interesting graph. It could be what I heard as the ported being a bit heavy handed in the 18-30 dB range in comparison. Subtle but its there. I think it would be definitely perceptible. The sealed seems like a flatter response overall.
Reply
Reply
post #7083 of 9696
9/21/12 at 12:16am
Quote:
Originally Posted by BrownTown View Post

What does the DUAL mode do on the XLR3 amp. Does it work both for RCA and XLR?
I am guessing it is for running two subs so how does it differ from slave mode?

The XLR3 allows two different modes of operation on the XLR jacks: 1- L & R SOURCE IN, and 2- SOURCE IN (mono) an LFE IN (mono). This allows the sub to be connected to two systems (say, a 2-channel music one, and a HT one) at the same time, without changing interconnects.

The XLR2 offers three modes of operation on XLR jacks, two of them involving MASTER and SLAVE. There is a pic of the silkscreens of both faceplates (XLR2 and XLR3) somewhere here on this forum. If you look at them carefully, the difference between the two will become apparent.
Reply
Reply
post #7084 of 9696
9/21/12 at 4:11am
Quote:
Originally Posted by nlpearman View Post

At one point a while ago, there was talk of Rythmik making a downward-firing 12" that was similar to the D15SE. Does anyone know if that's still potentially on the way?

Interesting. I was wondering the same thing but also was curious why we do not see more passive radiator designs. It appears that large 15 inch driver ported designs are the direction that sub companies are pursuing. That's fine for large rooms, but what about customers that have smaller rooms or just do not want the large box sub woofer? Wouldn't a 15 inch passive radiator design capture the best of both worlds? The smaller size of a sealed unit with the output and sound characteristics of a ported unit.

I understand the cost factor, but I feel that the customer who would purchase an internet direct sub is someone who is looking for quality first and would be willing to invest more for a superior product than a mass produced offering. However, is it possible that the DirectServo Rythmik design will not work as a passive radiator setup?

Brian, is it possible to offer a passive radiator DIY kit with plans?
Reply
Reply
post #7085 of 9696
9/21/12 at 7:37am
Thanks for the info BDP24, you are helping me out a lot. I am new to the home audio world. This is my first set of subs in the house, and the PSB's are my first home audio speakers. I cannot look at the back of an amp and tell you what the different modes do. I am trying to learn the fastest I can.

Now give me a car audio system and I can wire it up blindfolded biggrin.gif
Reply
Reply
post #7086 of 9696
9/21/12 at 7:57am
Quote:
Originally Posted by BrownTown View Post

Now give me a car audio system and I can wire it up blindfolded biggrin.gif

Blindfolded? Not my car!eek.gif
Reply
Reply
post #7087 of 9696
9/21/12 at 9:31am
Quote:
Originally Posted by H Stevens View Post

Interesting. I was wondering the same thing but also was curious why we do not see more passive radiator designs. It appears that large 15 inch driver ported designs are the direction that sub companies are pursuing. That's fine for large rooms, but what about customers that have smaller rooms or just do not want the large box sub woofer? Wouldn't a 15 inch passive radiator design capture the best of both worlds? The smaller size of a sealed unit with the output and sound characteristics of a ported unit.
I understand the cost factor, but I feel that the customer who would purchase an internet direct sub is someone who is looking for quality first and would be willing to invest more for a superior product than a mass produced offering. However, is it possible that the DirectServo Rythmik design will not work as a passive radiator setup?
Brian, is it possible to offer a passive radiator DIY kit with plans?
Passive radiators cost more than ports. It's fairly cheap to add a port. If I were to build a sub for myself, I'd build one with passive radiators.
Reply
Reply
post #7088 of 9696
9/21/12 at 11:30am
Brian can say for sure, but I cannot imagine why the servo would not work with a passive radiator. Might need a little tweaking of the feedback parameters but sealed, passive radiator or ported should all work fine. Passive radiators do cost quite a bit more than a port and I am not sure the value added by including them in the line. You might get a little more bass extension than ported with a little less control than sealed and a little smaller box...
Reply
Reply
post #7089 of 9696
9/21/12 at 12:33pm
Salk Sound has built units with passive radiators.
http://www.audiocircle.com/index.php?topic=69249.0

This is the only one I know of on the forums. I have seen it in person and it is gorgeous and really hefty. I did not get to hear it since his 5.1 is sitting in a closet until he builds his new theater room.
http://www.audiocircle.com/index.php?topic=72962.0;

The last paragraph sort of explains Brian's thoughts on passive radiators.
http://www.avsforum.com/t/1342986/rythmik-audio-fv15-hp-data-bass-test-results/120#post_20621885

Paul Spencer and Fatawan also have built horn variations using the Rythmik kits. I am not sure what their final impressions are and if they also sent their amps in for a modification afterwards.
Reply
Reply
post #7090 of 9696
9/21/12 at 2:16pm
Does anyone know of any isolation pads that will fit the FV15HP?
Reply
Reply
post #7091 of 9696
9/21/12 at 2:47pm
Great info on the passive radiators. I never saw those comments from Brian and he explains it really well.
Reply
Reply
post #7092 of 9696
9/21/12 at 7:07pm
Quote:
Originally Posted by Eldiablos View Post

Does anyone know of any isolation pads that will fit the FV15HP?
Auralex Gramma
Reply
Reply
post #7093 of 9696
9/21/12 at 11:58pm
Quote:
Originally Posted by BrownTown View Post

What does the DUAL mode do on the XLR3 amp. Does it work both for RCA and XLR?
I am guessing it is for running two subs so how does it differ from slave mode?

BT---The XLR2 and XLR3 faceplates are shown in Brian's posting in this forum on January 6th of this year, #4997 on page 167. He discusses the difference between the two, also.
Reply
Reply
post #7094 of 9696
9/22/12 at 5:42am
Quote:
Originally Posted by H Stevens View Post

Great info on the passive radiators. I never saw those comments from Brian and he explains it really well.

In vented subs, when we increase the number of ports from 1 to 2, the length of each port needs to double. The purpose of the port length is to create enough air mass loading for the Helmholtz resonators. Similar concept of mass loading applies to passive radiators. A single 15" passive radiator needs a moving mass of 500g or more. Going to larger diameter PR means even heavier loading mass. Now you can imagine the difficulty in dual opposing passive radiators. We need at least 1kg (2.2lbs) loaded mass in each of them. In the end it is difficult to find a reliable supplier to manufacture them. During transportation, we also need to be very careful to hold those passive radiators in place or they will move back and forth. All these consideration is why we still use ports.
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
post #7095 of 9696
9/22/12 at 7:40am
Thank you Brian, I would still be interested in building one just to enjoy the experience of doing it and testing the results. I think that a 12 inch Rythmik passive radiator design would be very interesting to build and test. Where could I obtain some info on where to purchase the radiators and enclosure design?
Reply
Reply
post #7096 of 9696
9/22/12 at 9:45am
I currently have a single F15HP clone (DS1510/H600PEQ3) that I use in my dedicated home theater. The theater dimensions are (13' x 20' x 8' - 8.5' (double tray ceiling)). I've been really happy with the single F15HP, but feel that I may be driving it close to it's limits at some points. We usually watch moves at around -8 dB. I have an onkyo 809 that I've calibrated using audessy multieq xt. I've taken some in room measurements using roomeq wizard that don't look too bad.

The question (probably for Brian) is if I built another F15HP clone using the H550PEQ3, is the phasing close enough to the H600PEQ3 so that I can drive them both off the same signal? The onkyo 809 has two subwoofer outputs, but they are essentially the same signal. I believe they're just using a splitter internally. Multieq XT obviously just treats them as one sub.
Reply
Reply
post #7097 of 9696
9/22/12 at 2:33pm
Quote:
Originally Posted by Skylinestar View Post

Auralex Gramma

Thank you very much!
Reply
Reply
post #7098 of 9696
9/22/12 at 3:46pm
Quote:
Originally Posted by Chupalt View Post

I currently have a single F15HP clone (DS1510/H600PEQ3) that I use in my dedicated home theater. The theater dimensions are (13' x 20' x 8' - 8.5' (double tray ceiling)). I've been really happy with the single F15HP, but feel that I may be driving it close to it's limits at some points. We usually watch moves at around -8 dB. I have an onkyo 809 that I've calibrated using audessy multieq xt. I've taken some in room measurements using roomeq wizard that don't look too bad.
The question (probably for Brian) is if I built another F15HP clone using the H550PEQ3, is the phasing close enough to the H600PEQ3 so that I can drive them both off the same signal? The onkyo 809 has two subwoofer outputs, but they are essentially the same signal. I believe they're just using a splitter internally. Multieq XT obviously just treats them as one sub.

Thinking about this more, I realize this is a stupid question. Any difference in phase between the two amplifiers will be minimal in comparison with difference caused by different in-wall cables and sub placement. The output capabilities should be close enough that they'll be a good match.
Reply
Reply
post #7099 of 9696
9/22/12 at 3:53pm
Actually, the electrical signal in the wires is probably traveling around half the speed of light or so (around 93,000 miles/sec). Unless the two speakers are many miles apart the cable delay is negligible. The acoustic delay, about 1 ms/foot, is the only thing that matters, and that is a function of where you place them.
Reply
Reply
post #7100 of 9696
9/22/12 at 8:12pm
The velocity factor of coax is actually closer to 0.7, but yeah I get what you're saying.
Reply
Reply
post #7101 of 9696
9/23/12 at 12:37pm
Depends on the coax. I have seen ~0.4 to over 0.9 in my (microwave) world. You are right that typical PE runs around 0.66 or so... Still well in excess of audio waves in air.
Edited by DonH50 - 9/23/12 at 12:55pm
Reply
Reply
post #7102 of 9696
9/24/12 at 5:36am
Quote:
Originally Posted by Chupalt View Post

The question (probably for Brian) is if I built another F15HP clone using the H550PEQ3, is the phasing close enough to the H600PEQ3 so that I can drive them both off the same signal? The onkyo 809 has two subwoofer outputs, but they are essentially the same signal. I believe they're just using a splitter internally. Multieq XT obviously just treats them as one sub.

The only differences between H550PEQ3 and H600PEQ3 are 1) the power filter cap, and 2) the transformer secondary voltage output. Everything thing else is identical. So that makes one way compatible. That is, the power amp board of H600PEQ3 can be used in H550PEQ3, but the power amp board of H550PEQ3 cannot be used in H600PEQ3.
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
post #7103 of 9696
9/24/12 at 8:42pm
I wonder if anyone here tested the high pass crossover in H600PEQ. This crossover should be of highest quality as it affects the quality of sound coming out of the rest of the system. It should be fast and what I call clean.

Having solved transformer problem I have recently tested the crossover in my H600PEQ, and unles I have a bad luck of having wrong value components in it, it's distorting the signal too much. If you feed the output to a headphone amp and listen via headphones it sounds really bad. The way around it is to use independent high pass crossover. I decided to use second order Bessel wirth 100Hz cut off frequency as a starting point because Bessel is fast (transients), has relatively low phase shift and is easy to build with standard component values. The difference is sweet honey against lemon with a touch od sugar.

Now, I'd like to know if it is some fault in my particular amp or it's a design problem, which should be fixed and luckily it's not difficult to do so.

cheers,
Reply
Reply
post #7104 of 9696
9/25/12 at 6:46am
Quote:
Originally Posted by janusz.pradzynski View Post

I wonder if anyone here tested the high pass crossover in H600PEQ. This crossover should be of highest quality as it affects the quality of sound coming out of the rest of the system. It should be fast and what I call clean.
Having solved transformer problem I have recently tested the crossover in my H600PEQ, and unles I have a bad luck of having wrong value components in it, it's distorting the signal too much. If you feed the output to a headphone amp and listen via headphones it sounds really bad. The way around it is to use independent high pass crossover. I decided to use second order Bessel wirth 100Hz cut off frequency as a starting point because Bessel is fast (transients), has relatively low phase shift and is easy to build with standard component values. The difference is sweet honey against lemon with a touch od sugar.
Now, I'd like to know if it is some fault in my particular amp or it's a design problem, which should be fixed and luckily it's not difficult to do so.
cheers,

The OPAMP we use for HPF (U1 in your H600PEQ) is OPA2134. It may not be the best sounding OPAMP (such as those OPA627 which are $30 a piece), but it should be ok sounding. Now OPA2134 does have a current limit around 16mA-20mA with plastic package. So its current capability is not as good as BUF03 or other headphone opamps. I am not sure about the distortion you refer to. If there is any, it can be easily checked out from the oscilloscope.
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
post #7105 of 9696
9/25/12 at 7:19pm
Sub by itself performs well. But once I have set up the system with signal taken from the high pass filter of H600PEQ the rest of the system did not perform as well as it did before the sub was included. "Satelite" spekers are 2x6nd430-16, audax hm-130co and morel et338.

First I tried volume and delay on the sub to improve output matching but it did not change much. My system is active and without the sub it performed very well except for the deep bass but it was designed to have a sub added one day. To eliminate any possible problems within my original system I plugged the output from the H600PEQ crossover into headphone amp and listened on headphones. Signal was distorted on music material but the degree of distortion depended on music material.

Very simple external second order Bessel solved the problem. Music played through Bessel via headphones was clean. Of course with lower frequencies gradualy dissapearing but very clean. So I think the problem is in the crossover in H600PEQ. I do not think it is the opamp. I do not know what order is the crossover in H600PEQ but if it is 4th order and capacitor values are not exactly as they shoud be that may be the problem. I can fix it but I'd need circuit diagram and pcb image of the crossover to avoid any mistakes and make it simple. If it's 4th order I'd change it to the 2nd order preferably Bessel. Simpler and cleaner than a 4th order crossover.

cheers,
Reply
Reply
post #7106 of 9696
9/25/12 at 7:30pm
Quote:
Originally Posted by janusz.pradzynski View Post

Very simple external second order Bessel solved the problem. Music played through Bessel via headphones was clean. Of course with lower frequencies gradualy dissapearing but very clean. So I think the problem is in the crossover in H600PEQ. I do not think it is the opamp. I do not know what order is the crossover in H600PEQ but if it is 4th order and capacitor values are not exactly as they shoud be that may be the problem. I can fix it but I'd need circuit diagram and pcb image of the crossover to avoid any mistakes and make it simple. If it's 4th order I'd change it to the 2nd order preferably Bessel. Simpler and cleaner than a 4th order crossover.
cheers,

The HPF on H600PEQ/PEQ2 is indeed 2nd order Bessel. The caps are 0.1uF, and the two resistors are 16kohm (from OPAMP output) and 22kohm (to OPAMP input) . That has a corner frequency of 85hz and Q value of 0.5863 (as compared with Bessel filter's Q value of 0.58).
Edited by Rythmik - 9/29/12 at 8:22am
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
post #7107 of 9696
9/26/12 at 1:20pm
F25 with H800XLR3

Brian,

Please update us on the status of the new F25. The wait has been quite long for its introduction since it was first mentioned over a year and a half ago.
Reply
Reply
post #7108 of 9696
9/26/12 at 3:04pm
Absolutely would love to hear any update on the F25 w/H800. Especially the DIY kits.

Any possibility of a higher powered version using the dual 1510s? Would the H800 be able to work fine with the 1505s? Personally like the appearance a little more.

Are the plans for the F25 available anywhere?
I plan to do a simple documentary of my second DIY journey and want to assemble a F25 kit.

Best Regards
KvE
Reply
Reply
post #7109 of 9696
9/29/12 at 6:27am
Quote:
Originally Posted by jheyau View Post

F25 with H800XLR3
Brian,
Please update us on the status of the new F25. The wait has been quite long for its introduction since it was first mentioned over a year and a half ago.

I am working with supplier to have this done as soon as they can. They ask for a 3 months lead time and I don't really think it needs that much time.
Quote:
Originally Posted by KMFDMvsEnya 
Any possibility of a higher powered version using the dual 1510s? Would the H800 be able to work fine with the 1505s? Personally like the appearance a little more.

They HX800 as what we will call it can work with any of our regular power drivers, DS1200, DS1501, DS1505. Right now the plan for dual DS1510 is on hold till I have all the products in the pipeline to complete.
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
Rythmik Insider
» Get the latest news and updates at the Rythmik sponsor page.
Reply
post #7110 of 9696
9/29/12 at 9:56pm
Man, sometimes this AV business kills me. Hoping my dream sub is finally out I check in on this thread. I marked my calendar for mid-September for the again delayed HX800 last time I checked this thread. I came today to see how it was being received by the first new owners. Months ago the "semi-official" expected date was about now and that was with a generous margin for error and a similar comment about "a few more months" back then. I see in the Rythmik reply above, however, that the HX800 amps may be yet another three months (but not really)? What?

Trying to be a loyal customer here but 1.5 years of putting off my sub purchases is getting old... and by now can it ever live up to the tortuous anticipation? biggrin.gif I hope this new F25/HX800 sub knocks the wind out of me after all of this waiting... since I want two maybe it will !
Reply
Reply
New Posts  All Forums:Forum Nav:
  Return Home

AVS Top Picks

AVS › AVS Forum › Audio › Subwoofers, Bass, and Transducers › Official Rythmik Audio Subwoofer thread