Official Rythmik Audio Subwoofer thread - Page 549 - AVS Forum
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post #16441 of 16736 Old 08-04-2014, 05:33 AM
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Originally Posted by laulau View Post
Here's a document that I did for a friend a few years back when he bought a Rythmik. It's an aggregation of info from numerous sources so I don't take any credit (or responsibility) for the information...none of it is etched in stone, so use or disregard any of the info, as you see fit. The document has evolved a lot since I originally did it and is decidedly Audyssey-centric, but if nothing else, it has a bunch of links to helpful references.

YMMV.

HTH
Wow, what a fantastic post. Thank you so much for pointing me to it.
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post #16442 of 16736 Old 08-04-2014, 05:38 AM
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Originally Posted by dazzdax View Post
Don and BDP, thanks for your replies. I have Soundlab A-1 electrostatic speakers and also 4 Rhytmik F-15's.
I have tried to get the best blending of the two sytems, but until now I haven't succeeded.
The 12dB/octave I like most, not the 24dB/octave. My main speakers have a cut off at about 40Hz with a natural slope of 12dB/octave.
With the F-15's I'm I've set the low pass cut off at 80Hz with 12dB/octave slope. Subwoofer level is very low (4 clicks from zero).

Chris
Ah, the big 'labs... Bearing in mind I last heard Soundlabs ages ago, I found their bass a bit "boomy", probably because it is hard for an amplifier to control such big panels. Back then a Decca ribbon was also a popular addition to help the highs. Anyway, I would play with rolling off the lows to the A1's to see what happens. Blending depends (among other things) upon getting the phase right at the crossover frequency so mains and sub(s) work together (are in phase) at the listening position (LP). Playing a test tone at the crossover frequency and adjust the Rythmik's phase knobs for maximum SPL at the LP is one way to do it. Measuring the impulse response is another, if you've the technical means and knowledge to do so. Away from the crossover, the sound does not instantly fade away, so there will be interaction among sub(s), main speakers, and room. I prefer to minimize interaction between sub and mains by using an active crossover to roll both off with a fairly high slope. If you are not doing that, integration may be more difficult, and placement of subs and mains is more important.

I would try rolling off the Soundlab's low end at 80 Hz with a high-pass filter (HPF) if you can, and moving the subs around (start in pairs because it's easier) to see if there is a sweet spot. You might try a lower crossover (e.g. 60 Hz) to reduce interaction at higher frequencies. Without measurements there will be more trial and error, but frankly with measurements it is still a lot of work to determine interactions among room, subs, and panels and how they relate to your ears at the listening position.

You should "feel" the subs more than "hear" them. The old rule of thumb was that if you hear them they are too loud. Actually that depends on the crossover, placement, and distortion in the subs, but still a useful reminder.

I understand your angst; a pair of big full-range ESLs and four subs is a lot of variables to manipulate. - Don

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #16443 of 16736 Old 08-04-2014, 05:56 AM
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Originally Posted by BDP24 View Post
I know that (qguy is the one looking), ya big silly. Say, how does Marchand achieve 24dB/octave passively?!
24 dB/octave implies fourth-order response, which can be achieved using two inductors (L's) and two capacitors (C's). For a LPF, you could start with a series L, then C to ground, then another L in series, then a final C to ground. For a HPF swap L's and C's. There are other ways but it has been a while since my filter design class. Choice of filter response is another variable (Butterworth, Bessel, Chebyshev, Elliptical, etc.) that affects amplitude response (roll-off, peaking, ripples in passband and/or stopband, and such) and phase response (linear or not, behavior through pass and stop bands, etc.)

Without op-amps a passive filter potentially has lower noise and distortion, assuming you are far away from saturating the inductors (i.e. they are run at low current, typical for line-level filters), but without active buffers the passive design is more sensitive to the source and load impedances since they will impact the filter's response. A common assumption is a low-impedance source and high-impedance load; a good company will specify the assumed source and load impedances beyond which the filter's response is no longer valid. The passive design will also have more loss, though some "active" designs may use unity-gain input and output buffers with a passive filter network inside (one of the buffers could be a gain stage, natch). It is usually easier to adjust the frequency corner of an active design (depending upon the filter topology you can do it with a single control; passive requires you to adjust L's and C's). Most passive designs I have seen are fixed at a single frequency determined by design.

Active or passive will work fine when properly designed and integrated. I have tended to use active as I appreciate the buffers to isolate source and load and you don't have to worry about the inductor's saturating or ringing. Of course, active circuits can ring too... L's tend to get large at audio frequencies, but passive does need a power supply. You can usually adjust an active design's frequency corner (and sometimes other parameters like gain, filter Q/bandwidth, etc.) though some active designs are fixed-frequency. And so forth, many trades.

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post #16444 of 16736 Old 08-04-2014, 06:33 AM
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Originally Posted by BigCoolJesus View Post
Any word on when some more F25's will be available? I have two in my room currently but thinking of adding two more.....

Or, what is the consensus on mixing sealed and ported subwoofers? Would adding two FV15HP's be a bad idea? Or maybe just two smaller F15HP's (sealed) to help smooth out response?

Thanks!
It's preferable to match, to help insure phase alignment at all frequencies. Be careful to set them all the filter settings the same. It's easy to make a mistake with a lot of subs, especially since the Rythmiks have a lot of adjustments.

Also, make sure you can time align them. I have a receiver with 2 sub outs, so I have the front 2 using sub 1 and the back to using sub 2. Without the time alignment, it's a mess.

I have a big room, but I liked going from two F25s to 4. Not as big as going from 1 to 2, but the seat to seat consistency improved and the extra subsonic headroom is fun.

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post #16445 of 16736 Old 08-04-2014, 06:58 AM
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Originally Posted by rcohen View Post
It's preferable to match, to help insure phase alignment at all frequencies. Be careful to set them all the filter settings the same. It's easy to make a mistake with a lot of subs, especially since the Rythmiks have a lot of adjustments.

Also, make sure you can time align them. I have a receiver with 2 sub outs, so I have the front 2 using sub 1 and the back to using sub 2. Without the time alignment, it's a mess.

I have a big room, but I liked going from two F25s to 4. Not as big as going from 1 to 2, but the seat to seat consistency improved and the extra subsonic headroom is fun.
I just read a helpful post concerning phase alignment determination. "There is a method for setting the phase control that guarantees perfect phase alignment between the subwoofer and main speakers. First, reverse the connections on your main loudspeakers so that the black speaker wire goes to the speaker’s red terminal, and the red speaker wire goes to the speaker’s black terminal. Do this with both speakers. Now, from a test CD that includes pure test tones, select the track whose frequency is the same as the subwoofer’s crossover frequency." My question is can I use this approach for phase alignment (even though I don't have a disk with pure test tones) by putting on a bass heavy track and altering the Rythmik phase alignment dial for when I hear the least bass?
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post #16446 of 16736 Old 08-04-2014, 08:33 AM
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Originally Posted by Cingulate Gyrus View Post
I just read a helpful post concerning phase alignment determination. "There is a method for setting the phase control that guarantees perfect phase alignment between the subwoofer and main speakers. First, reverse the connections on your main loudspeakers so that the black speaker wire goes to the speaker’s red terminal, and the red speaker wire goes to the speaker’s black terminal. Do this with both speakers. Now, from a test CD that includes pure test tones, select the track whose frequency is the same as the subwoofer’s crossover frequency." My question is can I use this approach for phase alignment (even though I don't have a disk with pure test tones) by putting on a bass heavy track and altering the Rythmik phase alignment dial for when I hear the least bass?
We're actually talking about two different things.


When matching a sub to mains, you want to match the phase at the crossover frequency. You should tune that for the most bass, not the least. Also, you would need to use a test tone or other technique that will let you look at the level of the crossover frequency at the listening position.


When matching subs with each other, you want to match phase at all frequencies. This can be tricky with different subs, since the phase can shift in a frequency dependent way.


Basically, if sound is coming from two sources, you want the phase to match, not cancel. With a crossover, sound comes from two sources at the crossover frequency. With two subs, sound comes from two sources at all frequencies below the crossover.


If your left, center, and right speakers are different, you may have similar problems.
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post #16447 of 16736 Old 08-04-2014, 09:08 AM
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Originally Posted by rcohen View Post
We're actually talking about two different things.


When matching a sub to mains, you want to match the phase at the crossover frequency. You should tune that for the most bass, not the least. Also, you would need to use a test tone or other technique that will let you look at the level of the crossover frequency at the listening position.


When matching subs with each other, you want to match phase at all frequencies. This can be tricky with different subs, since the phase can shift in a frequency dependent way.


Basically, if sound is coming from two sources, you want the phase to match, not cancel. With a crossover, sound comes from two sources at the crossover frequency. With two subs, sound comes from two sources at all frequencies below the crossover.


If your left, center, and right speakers are different, you may have similar problems.
You are right I am interested in making sure the phase alignment between the subwoofer and the mains is dialed in correctly. I have created a CD with 70hz pure test tones. That is the crossover for the subwoofer. Do you agree with the following methodology for making sure the phase alignment is set correctly?

"There is a method for setting the phase control that guarantees perfect phase alignment between the subwoofer and main speakers. First, reverse the connections on your main loudspeakers so that the black speaker wire goes to the speaker’s red terminal, and the red speaker wire goes to the speaker’s black terminal. Do this with both speakers. Now, from a test CD that includes pure test tones, select the track whose frequency is the same as the subwoofer’s crossover frequency. Sit in the listening position and have a friend rotate the subwoofer’s phase control until you hear the least amount of bass. The subwoofer’s phase control is now set perfectly. Return your speaker connections to their previous (correct) positions: red to red, black to black.

Here’s what’s happening when you follow this procedure. By reversing the polarity of the main speakers, you’re putting them out of phase with the subwoofer. When you play a test signal whose frequency is the same as the subwoofer’s crossover point, both the sub and the main speakers will be reproducing that frequency. You’ll hear minimum bass when the waves from the main speakers and subwoofers are maximally out of phase. That is, when the main speaker’s cone is moving in, the subwoofer’s cone is moving out. The two out-of-phase waves cancel each other, producing very little bass. Now, when you return your loudspeakers to their proper connection (putting them back in-phase with the subwoofer), they will be maximally in-phase with the subwoofer. (It's much easier to hear the point of maximum cancellation.) This is the most accurate method of setting a subwoofer’s phase control. Unless you move the subwoofer or main speakers, you need to perform this exercise only once."
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post #16448 of 16736 Old 08-04-2014, 11:06 AM
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That will work.

The way I have often suggested is sort of the inverse of that, playing a test tone and adjusting the phase to obtain the maximum reading (preferably on an SPL meter). That does not require swapping speaker leads. Theoretically either way works fine. The argument has been made that it is easier to hear a null than a peak, and that makes sense to me, so go ahead and dial it in per the procedure in your post.

Don't forget to swap the speaker connections back after setting the phase...

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post #16449 of 16736 Old 08-04-2014, 11:41 AM
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Oops...missed the part about reversing the connections. That makes sense.


Alternately, you could download a test tone app from the net or use REW to generate the test tone, and use a free/cheap SPL meter app in a smartphone.


Although a smartphone mic isn't "measurement quality," it's fine at telling you when you've maximized volume at the crossover frequency.
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post #16450 of 16736 Old 08-04-2014, 12:51 PM
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Just make sure the smartphone actually reaches down to the crossover with some decent signal level. Some smartphones roll off the mic around the vocal band to reduce noise so there's not much if any signal down at 50 - 100 Hz. The old iPhones rolled of in SW and actually made good measurements (once compensated); the newer ones added parts (HW) so it is a lot harder to get wideband accuracy, even for a relative measurement like this. A cheap $50 SPL meter is not a bad toy to have around.
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My understanding is I'm supposed to run Audyssey in one-port mode on my FV15HP and then, if I choose, convert the sub to two-port mode, because running Audyssey in two-port mode may lead to boosting of the missing ultra-low frequencies. Is that right? Isn't it a problem because two-port mode produces different sound and Audyssey won't have optimized for that?
This got buried in this fast-moving thread...

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post #16452 of 16736 Old 08-04-2014, 01:28 PM
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^^^Sometime's a bump is necessary
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Receiver - Denon 4311CI
Speakers - Infinity P363's, PC351, P153's
Subs - Rythmik FV15HP's
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post #16453 of 16736 Old 08-04-2014, 03:04 PM
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Once you run Audyssey as directed, any changes after that are for preference. The idea is to let Audyssey do its thing but leave you some wiggle room to adjust to taste. Same idea as running with the gain knob a little low so you can dial the bass up a little more if you wish.

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post #16454 of 16736 Old 08-04-2014, 03:54 PM
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Originally Posted by DonH50 View Post
Once you run Audyssey as directed, any changes after that are for preference. The idea is to let Audyssey do its thing but leave you some wiggle room to adjust to taste. Same idea as running with the gain knob a little low so you can dial the bass up a little more if you wish.
Interesting. You see why I ask, right? It's one thing to turn up the volume on the bass a little, it's another to change the frequency response of the sub, which is what you're doing by switching from 1-port to 2-port mode.

It's interesting that the concern is that running Audyssey in 2-port mode might lead Audyssey to boost the lowest frequencies, because presumably with most subs on the market, which don't go as low as the FV15HP does in 1-port mode, Audyssey isn't amping up those ultra-low frequencies (which would put tremendous stress on subs not designed to go that low).

So while this diagnosis seems to apply to not using the parametric EQ on the Rythmik before running Audyssey, I'm not clear on why it dictates running Audyssey in 1-port mode if one plans to use the sub in 2-port mode.

Educate me, more knowledgeable AVS denizens! Appreciated.

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Ideally, you would run room correction with the same setup you use to listen, but Audyssey needs to automatically detect the -3db natural rolloff point for your sub. If it doesn't properly detect that, it will try to boost where it shouldn't. If this happens, you may need a steeper rolloff setting for measurements, so Audyssey can detect the proper -3db point. The best bet is to measure the freq response before and after, to see if Audyssey did something weird.


Dirac lets you manually dial this stuff in.
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post #16456 of 16736 Old 08-04-2014, 05:25 PM
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Originally Posted by rcohen View Post
Ideally, you would run room correction with the same setup you use to listen, but Audyssey needs to automatically detect the -3db natural rolloff point for your sub. If it doesn't properly detect that, it will try to boost where it shouldn't. If this happens, you may need a steeper rolloff setting for measurements, so Audyssey can detect the proper -3db point. The best bet is to measure the freq response before and after, to see if Audyssey did something weird.


Dirac lets you manually dial this stuff in.
But if you're using two-port mode, presumably you want Audyssey to detect the natural rolloff *in two-port mode*, right? Am I missing something?

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post #16457 of 16736 Old 08-04-2014, 05:35 PM
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But if you're using two-port mode, presumably you want Audyssey to detect the natural rolloff *in two-port mode*, right? Am I missing something?
Yes, I'd think that would work fine, since the natural rolloff should be plenty steep. I saw someone warning about high damping, but not 2-port mode.


That said, when I auditioned an FV15HP, I much preferred the 1-port mode.
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post #16458 of 16736 Old 08-04-2014, 06:44 PM
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I do not remember the reason but Brian explained it in this thread, a search might help. It had something to do with Audyssey not properly measuring the lowest frequencies and thus applying unnecessary boost or something like that. Mine are sealed so I didn't really pay attention.

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post #16459 of 16736 Old 08-04-2014, 07:11 PM
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24 dB/octave implies fourth-order response, which can be achieved using two inductors (L's) and two capacitors (C's). For a LPF, you could start with a series L, then C to ground, then another L in series, then a final C to ground. For a HPF swap L's and C's. There are other ways but it has been a while since my filter design class. Choice of filter response is another variable (Butterworth, Bessel, Chebyshev, Elliptical, etc.) that affects amplitude response (roll-off, peaking, ripples in passband and/or stopband, and such) and phase response (linear or not, behavior through pass and stop bands, etc.)

Without op-amps a passive filter potentially has lower noise and distortion, assuming you are far away from saturating the inductors (i.e. they are run at low current, typical for line-level filters), but without active buffers the passive design is more sensitive to the source and load impedances since they will impact the filter's response. A common assumption is a low-impedance source and high-impedance load; a good company will specify the assumed source and load impedances beyond which the filter's response is no longer valid. The passive design will also have more loss, though some "active" designs may use unity-gain input and output buffers with a passive filter network inside (one of the buffers could be a gain stage, natch). It is usually easier to adjust the frequency corner of an active design (depending upon the filter topology you can do it with a single control; passive requires you to adjust L's and C's). Most passive designs I have seen are fixed at a single frequency determined by design.

Active or passive will work fine when properly designed and integrated. I have tended to use active as I appreciate the buffers to isolate source and load and you don't have to worry about the inductor's saturating or ringing. Of course, active circuits can ring too... L's tend to get large at audio frequencies, but passive does need a power supply. You can usually adjust an active design's frequency corner (and sometimes other parameters like gain, filter Q/bandwidth, etc.) though some active designs are fixed-frequency. And so forth, many trades.

For a 24dB low-pass, one is already built into the Rythmik plate amp---no need to make or buy one. For a 24dB high-pass, Marchand told me today that he can make the passive model 46XLR-A with that slope for $350. The 12dB version is $199. Bargains! For those big SoundLabs---the couple of times I've heard them (admittedly at shows, in huge rooms), the bass was very "wooly". It may be that the problem mating a pair of subs with them is their own loose bass, not a lack of integration between them and the subs. For that reason, and I may be in the minority here, I would actually try them crossed-over at 180Hz to a pair of the GR/Rythmik OB subs, using three of the 16 ohm drivers per side on one A370 amp. Easier on the panels and their amp, tighter bass.

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post #16460 of 16736 Old 08-04-2014, 07:46 PM
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I wanted more flexibility in setting the crossover (mine is not at 80 Hz) and the little dbx gave me what I wanted (and I had it anyway). It also ensured the HPF and LPF frequencies were identical, something harder to do with the knob on the sub (I have the equipment to determine it, but am lazy, and it is easier for me to measure the transfer function of a line-level box than set up my measurement mic and sweep the sub). Seems like there was another reason or two I went that route but it has been several years now and I don't actually recall all the reasons why. The quick guide for my 370PEQ2 is a little confusing on how the crossover controls and low-pass filter/slope controls play together. At one time I had it all figured out... It implies the HPF is fixed at 80 Hz and I do not recall if that is affected by the crossover knob (I''m thinking not but don't remember). I am not even sure how I left mine set; I think I had to use AVR/12 and set the crossover to max on the sub since I wanted to be able to use the phase control knob (which I believe is disabled in the LFE setting, the one I would have used) and the PEQ.

Ages ago with smaller panels I decided stereo subs were the way to go and have stuck with that (probably irrationally) ever since. Old habits... I am seriously considering adding another pair of Rythmiks to smooth my room response but (a) have treated the snot out of my room so it's fairly flat and (b) have one more kid to get through college (plus still helping out his older brother).

Marchand makes good stuff... I was thinking of going that route but needed the flexibility of variable frequency. The dbx was a gift and a unit I was familiar with so I took that route instead. Whilst kicking myself for not holding on to my old ARC crossover, or grabbing the Bryston I passed up decades ago.
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post #16461 of 16736 Old 08-04-2014, 09:52 PM
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Yes, I'd think that would work fine, since the natural rolloff should be plenty steep. I saw someone warning about high damping, but not 2-port mode.


That said, when I auditioned an FV15HP, I much preferred the 1-port mode.
Most folks seem to prefer one-port. It just occurred to me that in my somewhat cavernous space, the ultra low frequencies might not be doing as much for me, and the extra oomph of two-port mode might be welcome. But really, only one way to find out, I'll play around with this when I get a chance.
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post #16462 of 16736 Old 08-05-2014, 02:57 AM
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I wanted more flexibility in setting the crossover (mine is not at 80 Hz) and the little dbx gave me what I wanted (and I had it anyway). It also ensured the HPF and LPF frequencies were identical, something harder to do with the knob on the sub (I have the equipment to determine it, but am lazy, and it is easier for me to measure the transfer function of a line-level box than set up my measurement mic and sweep the sub). Seems like there was another reason or two I went that route but it has been several years now and I don't actually recall all the reasons why. The quick guide for my 370PEQ2 is a little confusing on how the crossover controls and low-pass filter/slope controls play together. At one time I had it all figured out... It implies the HPF is fixed at 80 Hz and I do not recall if that is affected by the crossover knob (I''m thinking not but don't remember). I am not even sure how I left mine set; I think I had to use AVR/12 and set the crossover to max on the sub since I wanted to be able to use the phase control knob (which I believe is disabled in the LFE setting, the one I would have used) and the PEQ.

Ages ago with smaller panels I decided stereo subs were the way to go and have stuck with that (probably irrationally) ever since. Old habits... I am seriously considering adding another pair of Rythmiks to smooth my room response but (a) have treated the snot out of my room so it's fairly flat and (b) have one more kid to get through college (plus still helping out his older brother).

Marchand makes good stuff... I was thinking of going that route but needed the flexibility of variable frequency. The dbx was a gift and a unit I was familiar with so I took that route instead. Whilst kicking myself for not holding on to my old ARC crossover, or grabbing the Bryston I passed up decades ago.

Ooh, the Bryston is awesome. It oughta be, for what they charge for it! For years I was dead set against any active electronics between amps and ESL's (because of their transparency), and so had a simple passive 6dB/octave R/C on the input jacks of my power amp. I'm much less dogmatic in my advancing years, more pragmatic.
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Most folks seem to prefer one-port. It just occurred to me that in my somewhat cavernous space, the ultra low frequencies might not be doing as much for me, and the extra oomph of two-port mode might be welcome. But really, only one way to find out, I'll play around with this when I get a chance.
Yeah, I'd say turn Audyssey off so it doesn't interfere, and experiment with the ports and filter settings to see what you like.

If you don't hear much difference in your room, go with the more efficient settings.

After you have your favorite, re-run Audyssey.
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post #16464 of 16736 Old 08-05-2014, 05:09 AM
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Ooh, the Bryston is awesome. It oughta be, for what they charge for it! For years I was dead set against any active electronics between amps and ESL's (because of their transparency), and so had a simple passive 6dB/octave R/C on the input jacks of my power amp. I'm much less dogmatic in my advancing years, more pragmatic.
Unless something is broken, and despite ESL's (or Magnepan's) low distortion compared to other speakers (relatively, sometimes), the distortion added by even a long chain of electronics before the amp is in the mud. The amplifier normally dominates the distortion of the electronics chain, and it is still normally an order of magnitude or two lower than the speakers themselves.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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Most folks seem to prefer one-port. It just occurred to me that in my somewhat cavernous space, the ultra low frequencies might not be doing as much for me, and the extra oomph of two-port mode might be welcome. But really, only one way to find out, I'll play around with this when I get a chance.
I've experimented a lot with both modes. If you have a large space to fill and only have a single FV15HP I highly recommend 2 port mode. It has noticeably more output and you can run the sub hotter without having to worry about running into any port noise. With that said, I now have dual FV's and run both in single port mode low dampening with a +3db boost at <60hz using the PEQ on the amp. My living room is >5000 cu ft completely exposed to an upstairs loft and formal dining room.

Receiver - Denon 4311CI
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I've experimented a lot with both modes. If you have a large space to fill and only have a single FV15HP I highly recommend 2 port mode. It has noticeably more output and you can run the sub hotter without having to worry about running into any port noise. With that said, I now have dual FV's and run both in single port mode low dampening with a +3db boost at <60hz using the PEQ on the amp. My living room is >5000 cu ft completely exposed to an upstairs loft and formal dining room.
For what it's worth, in order to get Audyssey to set the sub at -5, after which I raised it to -1, the sub gain is actually a little below midnight, so it's not like I'm running things particularly hot. Since that's the case, is there any benefit to 2-port over 1-port mode, to outweigh the downside of less ULF content?
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For what it's worth, in order to get Audyssey to set the sub at -5, after which I raised it to -1, the sub gain is actually a little below midnight, so it's not like I'm running things particularly hot. Since that's the case, is there any benefit to 2-port over 1-port mode, to outweigh the downside of less ULF content?
20hz and up 2 port offers better composure and more output. I recommend 2 port if you have a large space to fill and like the bass hot, but only run 1 FV. Now if you have duals you have more headroom and can run single port mode. *Disclaimer this was the route I took in my particular situation and it worked best for me. I don't have a dedicated theater room.
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20hz and up 2 port offers better composure and more output. I recommend 2 port if you have a large space to fill and like the bass hot, but only run 1 FV. Now if you have duals you have more headroom and can run single port mode. *Disclaimer this was the route I took in my particular situation and it worked best for me. I don't have a dedicated theater room.
Well, I currently run my sub 4 db hot and I'm undecided between that and 3 db hot, so I don't know that I meet your criteria for liking it hot. And I don't play at reference levels. At non-reference levels, with plenty of headroom in 1-port mode, is there any benefit to 2-port? I'm still struggling to get my head around that.
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Well, I currently run my sub 4 db hot and I'm undecided between that and 3 db hot, so I don't know that I meet your criteria for liking it hot. And I don't play at reference levels. At non-reference levels, with plenty of headroom in 1-port mode, is there any benefit to 2-port? I'm still struggling to get my head around that.
I found that 1-port mode dug deeper and made the bottom octave more detailed, especially when combined with 14-hi damping.

They bring up good points, though, that if you run out of headroom, 2-ports and more efficient filter settings may be better for your room.
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post #16470 of 16736 Old 08-06-2014, 05:32 AM
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Well, I currently run my sub 4 db hot and I'm undecided between that and 3 db hot, so I don't know that I meet your criteria for liking it hot. And I don't play at reference levels. At non-reference levels, with plenty of headroom in 1-port mode, is there any benefit to 2-port? I'm still struggling to get my head around that.
If your not listening at reference level and only running +4db hot you should be golden (unless you are getting port noise). Why miss out on that 12hz content if your happy with what you hear right now? The only way to satisfy your curiosity about 2 port mode is to try it out for yourself. How big is your room I forget?

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