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Topic: Subwoofer set up (Read 26056 times) previous topic - next topic
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Subwoofer set up

While many subs offer high and low level inputs, afaik REL is the only one that strongly recommends using high level input from the amp speaker terminals even where the amp offer a line level sub out.
Presumably amps offer these at a fixed crossover - 80hz in the case of one that I know. Using this would mean that the main speakers get no information below that, sub gets no information above, while in the case of high level connections the main speakers would still go as low as they are able to, the sub would also get all the content, leaving the crossover setting in the sub to decide the level below which the sub would reinforce as opposed to replace what the main speakers do.
In the above example, where the main speakers don't go below 90hz or so, low level usage would leave a hole in the sound. But where they go down to say 50hz, what is the difference in sound between using high and low level inputs? Does the REL recommendation apply for every sub that offers this option?
REL also suggests using as low a crossover and as high a sub output as possible as a starting point to optimising the sub performance. Would this apply to other subs that accept high level inputs as well?

Subwoofer set up

Reply #1 –
REL suggestion of using speaker level input has both advantages and disadvantages.

For movies predominantly, it's preferable to use the Line Input from the surround processor / preamp / receiver as this is how movies have been designed.

For music predominantly, use the line level to extend the bass of your main system, whilst enabling them to produce a limited band of frequencies, which allows them to work more optimally. The disadvantage is that it is really preferable to use two subs with this approach, each positioned optimally for a fairly flat in-room frequency response

Simon
Elmura Audio Visual (Australia)

Subwoofer set up

Reply #2 –
Quote from: elmura on
REL suggestion of using speaker level input has both advantages and disadvantages.

For movies predominantly, it's preferable to use the Line Input from the surround processor / preamp / receiver as this is how movies have been designed.

For music predominantly, use the line level to extend the bass of your main system, whilst enabling them to produce a limited band of frequencies, which allows them to work more optimally. The disadvantage is that it is really preferable to use two subs with this approach, each positioned optimally for a fairly flat in-room frequency response

Simon
Elmura Audio Visual (Australia)

For movies, assuming you are referring to the LFE input fed from the AVR, I understand - REL subs have a LFE input in addition to the other two, and recommend using it for movies.
Does taking away some of the lowest end content that main speakers are able to deliver, allow them to deliver better SQ from the rest of the content? Yes is what you are suggesting, I take it.
REL on the other hand claims that getting the entire sonic signal into the sub via the high level inputs allows for better integration with the main speaker sound.
If so, I suppose it depends on how much the benefit from one offsets that from the other, because they seem to be mutually exclusive.
Would using the REL approach do away with the preference for two subs?

Subwoofer set up

Reply #3 –
Surely it doesn't matter. The crossover is either in the sub for high level inputs or in the AVR? LFE is different as it's a separate track. But for music do some AVRs send the bass below the crossover frequency out of this output? If you've got a sub/sat setup they must do surely?

Subwoofer set up

Reply #4 –
I was a REL dealer, so I am familiar with their propaganda. Their argument why they advise using high level inputs is complete BS. They are of the mind (or at least promote the concept) that amps have different "sonic signatures" and that you want to preserve that in the signal you send to the sub [hence preamp level signals "won't do"]. This is typical high-end audiophile mythology. All competent amps are in truth transparent and have no "signature" or transfer function to speak of. Meanwhile, by using this antiquated method which hasn't been common since the 1980s you don't free up the burden of reproducing the low bass by the main speakers, nor the main amp [both receive a full range signal], they expect you to set the crossover on the sub by ear since you no longer can rely on the receiver or prepro to set it to the same value that the main speakers are being filtered at, and no "bass management" occurs. Oh, and if your setup has a self calibration system like Audyssey XT/32 or YPAO?  You can't use them properly because they don't address the low bass with extra attention and a dedicated expanded set of filters if it's simply part of the main front channels, it has to be a dedicated subwoofer out signal, otherwise that entire set of filters [512x the number of earlier Audyssey systems, for example] lies dormant and isn't utilized.

Subwoofer set up

Reply #5 –
Quote from: mzil on
They are of the mind (or at least promote the concept) that amps have different "sonic signatures" and that you want to preserve that in the signal you send to the sub [hence preamp level signals "won't do"]. This is typical high-end audiophile mythology. All competent amps are in truth transparent and have no "signature" or transfer function to speak of. Meanwhile, by using this antiquated method which hasn't been common since the 1980s

I thought the thinking was more to do with getting the entire sound content into the sub and not the sonic signature of any particular amp. And if they have both inputs available on their sub, what would they gain in promoting the use of the high level one even where the amp offers a line level sub out? If the amp out is designed to cross over lower than what the main speakers can deliver, would the REL approach in this case not be better so as to not leave a hole in the sound?
Generally speaking, do subs that offer high level inputs do so only to cater to integrated amps that don't have line level sub out jacks?

Subwoofer set up

Reply #6 –
Quote from: KumarK on
would the REL approach in this case not be better so as to not leave a hole in the sound?


But they'll have to low-pass it anyway so it's either got to be done in the amp or the sub ( built-in amp).

Subwoofer set up

Reply #7 –
Quote from: probedb on
Quote from: KumarK on
would the REL approach in this case not be better so as to not leave a hole in the sound?


But they'll have to low-pass it anyway so it's either got to be done in the amp or the sub ( built-in amp).

If the speakers can deliver only down to 100hz and the amp passes on only lower than 80hz to the sub via the sub out, wiring the amp speaker terminals to the sub would allow the sub to receive the missing content, and setting the sub crossover to 100hz or above would address the issue.
Does the use of the high level connections make sense only in such cases? And in the case of a pre/power, can one wire the line level output from the pre to the line level input on the sub to the same effect?

Subwoofer set up

Reply #8 –
Quote from: KumarK on
If the speakers can deliver only down to 100hz and the amp passes on only lower than 80hz to the sub via the sub out, wiring the amp speaker terminals to the sub would allow the sub to receive the missing content, and setting the sub crossover to 100hz or above would address the issue.
Does the use of the high level connections make sense only in such cases? And in the case of a pre/power, can one wire the line level output from the pre to the line level input on the sub to the same effect?


I guess I'm coming from the AVR world which generally have controllable crossovers, usually 80-120Hz? So that isn't an issue, besides if you know your speakers only go to 100Hz, you're not going to be using a crossover at 80Hz. I'm not sure of any dedicated stereo amps that have dedicated sub-outs? I could be wrong though.

I think this is more about promoting high level as being better than the dedicated out. If you only have a stereo amp you usually only have high level anyway.

Subwoofer set up

Reply #9 –
I've always wondered about the REL system. My T2 sub was the first part of my stereo when I started to go off the audiophile deep end and I totally drank the koolaid too. While I never understood the technical difference in using the high-level connection, I always thought it was more about matching the gain of the amp at any volume level, not so much for any other reason.

Subwoofer set up

Reply #10 –
Quote from: Hotsoup on
I've always wondered about the REL system. My T2 sub was the first part of my stereo when I started to go off the audiophile deep end and I totally drank the koolaid too. While I never understood the technical difference in using the high-level connection, I always thought it was more about matching the gain of the amp at any volume level, not so much for any other reason.

I don't think it is anything about REL as such - what they suggest should apply just as well to any sub that has a choice of high and low level inputs and quite a few makes do offer that choice. I have no idea about what they recommended for best results.
Matching the gain may be the reason, but this must be getting accomplished with low level inputs as well - it has to.
Hopefully someone will soon shed light on this question for the benefit of less knowledgeable people like me.

Subwoofer set up

Reply #11 –
If you have a 5.1 or 7.1 receiver, I recommend using the line-level subwoofer output, especially if you watch 5.1/7.1 movies.

The "point one" Low Frequency Effects Channel ONLY goes to the subwoofer and is NOT sent two the front or surround speakers and is not included in the downmix when you are in stereo mode.  If you use REL's suggestion, you'll loose the LFE channel from movies and only get the regular bass from the stereo & surround channels.* 

Your 5.1/7.1 receiver will have optional bass management (an active crossover) so you can route the "regular" bass from the other 5 (or 7 channels) to the sub.    Sometimes there is a setting on the receiver for "speaker size", and the implication is that if you have large front & surround speakers, they can handle the normal bass, and only the low frequency effects will go to the sub.  If you choose the "small" setting, you'll turn-on the crossover and send ALL of the bass to the sub.  (That's the most common setup).


* The Wikipedia article is wrong when it says the LFE will be sent to your main speakers....  It will be lost if you don't a subwoofer.    That doesn't mean you won't get any bass, it just means you won't get the extra kick from "booms & explosions".  You check the Dolby website to confirm this, or try to find a test or setup DVD/Blu-Ray disc to check it yourself.  I have test/demo DVD from Dolby, but unfortunately they no longer sell it.

Subwoofer set up

Reply #12 –
Quote from: DVDdoug on
If you use REL's suggestion, you'll loose the LFE channel from movies and only get the regular bass from the stereo & surround channels.*

REL are quite clear in saying that for movies, the LFE input on the sub should be used - the third one they have on their subs.
My questions in this thread are for stereo music sound only.

Subwoofer set up

Reply #13 –
REL FAQ page: "Should I use High Level Input Connection or Low Level Input Connection?

Unless your amplifier does not allow for High Level Connection we always recommend using the High Level Connection. The purpose of using the High Level Input, instead of the Low Level Input, and connecting to the speaker output terminals is one of the unique secrets of REL's success. By connecting to the high-level input on the REL from the amplifier you build forward the sonic signature of your main system, including the tonal balance and timing cues of the entire electronics chain. In the way, the REL is fed the exact signal that is fed to the main speakers. This is a very important point and together with REL's Active Bass Controller (ABC), ensures far superior system integration of the sub-bass with the main system."

"Can high and low level circuits be used at the same time?

No, it is not effective to use the High Level Input concurrently with the Low Level Input. Where possible, please connect the High Level Input to your main L-R amplifier channels and set the processor (in a home cinema system) to Full Range or Large in the Speaker Set-up Menu. Using the High Level Input and connecting to the speaker output terminals is one of the unique secrets of REL's success and will maximize sub-bass performance."


Hmmm, "Unless your amplifier does not allow for High Level Connection" must be for all the people with power amplifiers which don't have, um, speaker outputs!(?)

Subwoofer set up

Reply #14 –
I always wondered what makes REL subs "superior" to other brands and today I just learn from their FAQ page one of the reasons (that strangely never got mentioned in any of the training sessions I attended while a dealer): their decision not to use cheap, white paint on a black background for the control knobs on the rear panel, pardon me, "rear apron" as the Brits would call it:

"Many speaker companies sell subs with their own speakers, why should I buy a REL instead of the "matching" subwoofer?

The notion that a full range speaker manufacturer might make a "matching" sub to the main speakers is a flawed premise. Sub-bass may be the most demanding design brief in all of speaker design and the ability to do it well and reliably is beyond the abilities of almost all speaker manufacturers. The easiest way to tell if a subwoofer is a result of happenstance is to turn the sub around and look at the rear panel. Most possess low quality connectors that will oxidize and start humming in a few months or year, and usually use cheap black paint with white graphics. These are telling signs that the subwoofer was designed to produce a salable object for the lowest cost to the manufacturer. Moreover, these subwoofers usually feature drivers designed NOT to produce deep bass, a poor quality amplifier, and lack true filter capability or technology. While these subwoofers are a profit center for the manufacturer, they should be avoided at almost any cost. Stay with a specialist mark such as REL. All we want is the opportunity to show you why the .1 in 5.1 should be remarkable."

For those of you who might not know how they actually stack up to the competition:

SVS sub PB-2000 $800 MSRP:



REL sub R-328 $1800 MSRP



Source: http://www.soundandvision.com/content/rel-...t-labs-measures

Subwoofer set up

Reply #15 –
I'm wondering too if there's any veracity to their nuetrik high-level connection vs. typical line-level for strictly 2.0 stereo. Assuming crossover is set the same, volume matched too, would the two setups behave differently?

I've been happy with my T2 but mzil's graph of the R-328 makes me question....

Subwoofer set up

Reply #16 –
Quote from: KumarK on
While many subs offer high and low level inputs, afaik REL is the only one that strongly recommends using high level input from the amp speaker terminals even where the amp offer a line level sub out.
Presumably amps offer these at a fixed crossover - 80hz in the case of one that I know. Using this would mean that the main speakers get no information below that, sub gets no information above,


No, it would never mean that.  Such a case would mean an infinite crossover slope, which is practically impossible.  Both speakers will put out some sound outside their nominal pass band.  Often this can be fairly large when the crossover slopes are low.
Ed Seedhouse
VA7SDH

Subwoofer set up

Reply #17 –
Quote from: Hotsoup on
I'm wondering too if there's any veracity to their nuetrik high-level connection vs. typical line-level for strictly 2.0 stereo. Assuming crossover is set the same, volume matched too, would the two setups behave differently?

I've been happy with my T2 but mzil's graph of the R-328 makes me question....

I used REL as just an example of why high level is supposedly used - not to endorse REL sound in any way. Or the opposite. My question was for high level connections in general for stereo music play, testing the REL recommendation as a general guideline for any sub that has both inputs.

Quote from: Ed Seedhouse on
No, it would never mean that.  Such a case would mean an infinite crossover slope, which is practically impossible.  Both speakers will put out some sound outside their nominal pass band.  Often this can be fairly large when the crossover slopes are low.

I understand that the cut off cannot be digital - I did not know the term to use: crossover slope, so I did not say it right. Even where both speakers put out some sound outside their bands, if there is enough of a distance between the band limits, there will be a gap affecting sound delivered. For such a amp/speaker combination, high level connections seem to be the only way out.
But where the bands overlap, is there any benefit in using high level?

Subwoofer set up

Reply #18 –
Quote from: DVDdoug on
* The Wikipedia article is wrong when it says the LFE will be sent to your main speakers....  It will be lost if you don't a subwoofer.    That doesn't mean you won't get any bass, it just means you won't get the extra kick from "booms & explosions".  You check the Dolby website to confirm this, or try to find a test or setup DVD/Blu-Ray disc to check it yourself.  I have test/demo DVD from Dolby, but unfortunately they no longer sell it.


It depends.  Some systems can be set such that dedicated 'subwoofer' LFE output (as well as bass from any 'SMALL' speakers)  is rerouted to 'LARGE' speakers.  That's the way bass management was supposed to work.  But it's inconsistently implemented.  It also might not be a great idea to do it, since explosive LFE content can be stressful to 'main' speakers.

Subwoofer set up

Reply #19 –
Quote from: mzil on
I was a REL dealer, so I am familiar with their propaganda. Their argument why they advise using high level inputs is complete BS.


Agreed.

Quote
They are of the mind (or at least promote the concept) that amps have different "sonic signatures" and that you want to preserve that in the signal you send to the sub [hence preamp level signals "won't do"]. This is typical high-end audiophile mythology. All competent amps are in truth transparent and have no "signature" or transfer function to speak of.


I don't know how they arrived at their anti-scientific conclusions but that sounds probable. IME their subs are poor values. Bad science costs!


Quote
Meanwhile, by using this antiquated method which hasn't been common since the 1980s you don't free up the burden of reproducing the low bass by the main speakers, nor the main amp [both receive a full range signal],


Excellent points!

Quote
they expect you to set the crossover on the sub by ear since you no longer can rely on the receiver or prepro to set it to the same value that the main speakers are being filtered at, and no "bass management" occurs.


IME the bass management on modern receivers has been a real step foreward in terms of sound quality.

Quote
Oh, and if your setup has a self calibration system like Audyssey XT/32 or YPAO?  You can't use them properly because they don't address the low bass with extra attention and a dedicated expanded set of filters if it's simply part of the main front channels, it has to be a dedicated subwoofer out signal, otherwise that entire set of filters [512x the number of earlier Audyssey systems, for example] lies dormant and isn't utilized.


That may be controversial. The various self-calibration schemes vary in terms of what they attempt and what they accomplish. I've seen real world measurements measurements on AVS that suggest that the more sophisticated schemes such as Audyssey XT32 are effective with subwoofers, which is one thing that makes them more costly to implement.  Rather than spend the big bucks on a high end AVR with Xt32 on it, I reached into my store room and added a couple of pro audio multiband parametric eq to my subwoofers with good results.

One of the newer great values in high quality tools for room tuning is the MiniDSP which has banks of effective filters that you control via USB with a PC. They start out in the $100-150 range and are highly recommended by many. I have one on hand but I have not had time to install it.

My long term goal is to expand from 2 12" subwoofers each with individual location and equalization tuning to add a dual 15" sub based on some drivers from Stereo Integrity and using the MiniDSP to eq the whole assembly. Frankly, the 2 12s (one Paradigm and one Cambridge Soundworks) work out very well for and have been tunable to produce fairly uniform strong deep bass across a fairly wide range of listening locations.

My listening room is a composite of 3 adjoining rooms that have very large openings into each other and a large open doorway into a very large hallway, and has thick wet plaster walls and ceiling as well as a wood parquet over concrete slab foor, so it does not waste bass energy like a typical stick built house with thin drywall. but it does enclose a large space.

Subwoofer set up

Reply #20 –
Quote from: Arnold B. Krueger on
One of the newer great values in high quality tools for room tuning is the MiniDSP which has banks of effective filters that you control via USB with a PC. They start out in the $100-150 range and are highly recommended by many.


That price would be for stereo only, but as far as I know to at least partly replicate an Audyssey XT32 5.1/7.1 ch AVR's functionality, including EQ of all channels with the supplied mic, you would need to spend $570 USD for a miniDSP 10x10 Hd + UMIK-1, plus this would only work with an existing setup which used outboard power amps for each of the 5/7 channels, not common for people attempting to integrate with introductory receivers inexpensively, for example.

Or their nanoAVRDL + UMIK-1 + Dirac license (so the system has full functionality beyond the 24 hours trial use) might be better for those who want to use digital HDMI sources, two only, at about $620 but that would limit one to an only 2 HDMI source device system, plus you need to buy an AVR with at least one HDMI in to go with it.

A factory refurbished Audyssey XT32 Onkyo receiver, on the other hand, with full, auto self calibration can be had for $600, with nothing extra to buy except for speakers and sources, or if one insists on new, a Denon Audyssey XT/32 AVR-4000 can be had for $800, or so.

Many Audyssey XT32 systems also calibrate for 2 subs at different levels and placed at different distances [although the EQ itself is just for the two summed together, fine by me] and their option for automatic, variable, equal loudness contour correction based on the measured SPL at the main listening position is the best I have ever heard short of dialing it in manually by ear myself, each and every time I modify the level [not happening], although there is a learning curve of figuring out which level offset to invoke for the given input you are using since the average sound level for sources such as cable TV vs. bluray/DVD, for example, differ.

I also think the need to purchase two subs, instead of one, to even out the room frequency response compared to a one sub system, is greatly diminished these days thanks to auto calibration systems such as Audyssey's, with their clever averaging of up to eight measured locations. My single sub sounds just fine to me and seems to be very well integrated.

To the best of my knowledge commercial movie theaters, which have to cover a *huge* range of seated positions, are usually run with just one sub.

Subwoofer set up

Reply #21 –
Quote from: mzil on
That price would be for stereo only, but as far as I know to at least partly replicate an Audyssey XT32 5.1/7.1 ch AVR's functionality, including EQ of all channels with the supplied mic, you would need to spend $570 USD for a miniDSP 10x10 Hd + UMIK-1, plus this would only work with an existing setup which used outboard power amps for each of the 5/7 channels, not common for people attempting to integrate with introductory receivers inexpensively, for example.

The MiniDSP 2x4 is 2 in 4 out rather than "stereo" per se. Even inexpensive receivers (eg Pioneer VSX-824K $350-400) have dual sub outs (may not be "stereo", not sure) that can be fed to the 2x4 and feed 4 subs, which is usually enough. The signal will already be low passed by the bass management. Each channel can be independently EQ'd and delayed (with further filtering if needed). $125.
And you can still utilize the MCAA type processing for the 5chs, if desired.

Quote from: mzil on
I also think the need to purchase two subs, instead of one, to even out the room response compared to a one sub system, is greatly diminished these days thanks to auto calibration systems such as Audyssey's, with their clever averaging of up to eight measured locations. My single sub sounds just fine to me and seems to be very well integrated.

Unless the sub is nearfield, or the room extremely lossy/damped (i.e several feet thickness) it will be practically  impossible to get smooth response over a wide area. Audyssey may average the measured responses, but it cannot spatially apply those (to each position). There will still be variations at each location due to (room/speaker) modal interaction.
For smooth averaged pressure over a wide area, you need spatial averaging afforded by multiple sources (subs). At least for HT.
For stereo music, things are a bit trickier. 2 subs are a must (at least to 40hz or so) and good integration with the mains. Or better yet, mains capable of 40hz extension.
And then there is beyond just smooth pressure for high quality bass reproduction, but that's for another day. 

cheers,

AJ

Loudspeaker manufacturer

Subwoofer set up

Reply #22 –
Quote from: mzil on
Quote from: Arnold B. Krueger on
One of the newer great values in high quality tools for room tuning is the MiniDSP which has banks of effective filters that you control via USB with a PC. They start out in the $100-150 range and are highly recommended by many.


That price would be for stereo only, but as far as I know to at least partly replicate an Audyssey XT32 5.1/7.1 ch AVR's functionality, including EQ of all channels with the supplied mic, you would need to spend $570 USD for a miniDSP 10x10 Hd + UMIK-1, plus this would only work with an existing setup which used outboard power amps for each of the 5/7 channels, not common for people attempting to integrate with introductory receivers inexpensively, for example.


Those facts are indisputable for the general case, but while I may not have been clear enough about it, the context was subwoofers in which case the 2.4 version at the price I mentioned seems like a great tool for a great price.

Virtually every mainstream AVR comes with some kind of system optimization tool thqat works over much of the midrange so there is usually no need to try to duplicate it. Equalizing subwoofers is a different matter.

Quote
A factory refurbished Audyssey XT32 Onkyo receiver, on the other hand, with full, auto self calibration can be had for $600, with nothing extra to buy except for speakers and sources, or if one insists on new, a Denon Audyssey XT/32 AVR-4000 can be had for $800, or so.


I'll pass on the Onkyo because I depend on HDMI sources and Onkyo has a bad corporate reputation when it comes to HDMI. The $600 refurb jas XT32 it does not have the full  implementation of subwoofer eq, if memory serves. AFAIK the lower two or three versions of Audysey are pretty thin when it comes to subwoofer support. Even the top models don't handle multiple subwoofers beyond two, and not thoroughly well at that.  So, the $800 model would be the alternative if subwoofer equalization would be desired.

Quote
I also think the need to purchase two subs, instead of one, to even out the room frequency response compared to a one sub system, is greatly diminished these days thanks to auto calibration systems such as Audyssey's, with their clever averaging of up to eight measured locations.


I don't know why that would be. It is not uncommon for subwoofer coverage to contain black holes for bass, whose correction y means of equalization should never be attempted in the first place because they can be infinite energy sinks. These are often not in the low frequency extremes so filling them in with a correctly placed subwoofer that has only modest performance is possible.

Quote
My single sub sounds just fine to me and seems to be very well integrated.


Good!  Too bad there is no rule saying that is generally true.

Quote
To the best of my knowledge commercial movie theaters, which have to cover a *huge* range of seated positions, are usually run with just one sub.


It's a relatively large professionally designed purpose built room often the size of a small performance hall, and there is no real comparison between its performance and needs  and your typical audiophile listening room.  The Schroeder frequency, which is highly relevant to bass response, is far lower in concert halls than listening rooms, for example.

Subwoofer set up

Reply #23 –
Quote from: ajinfla on
Audyssey may average the measured responses, but it cannot spatially apply those (to each position).


I'm not getting your use of the word "spatially". :confusion: Please explain.

I would use it in acoustics to mean, for example, "The two identical speakers sitting right next to each other, 8 feet in front of me in this anechoic chamber, sound discernibly different, at least in perceived direction, only because spatially one is a few degrees horizontally to the left of the other one."

I don't think you are using "spatially" in that same sense but I don't understand what you do mean. Please elaborate, thanks.

Subwoofer set up

Reply #24 –
Quote from: mzil on
I don't think you are using "spatially" in that same sense but I don't understand what you do mean. Please elaborate, thanks.

With a single sub you will have quite a bit of FR variance at each location (seat) in a multi-seating setup. Rather than apply a single "fix" EQ for one location, that will be incorrect for the others, Audyssey measures at multiple locations and applies a single averaged "fix" to the sub, which will supposedly smoothen the response somewhat at each seat, but never to the extent that it could for one seat only. There can still be (relatively large) peaks and dips in the response). The result will never be as smooth as multiple sources exciting the room, where the sources themselves, causes averaging out of those peaks and dips, which is then further smoothened with averaged EQing.
The multi-sub approach will yield smoother pressure response over the same spatially displaced listening positions, than any single sub. That's what the Harman/Geddes approach (which I'm sure you're familiar with) is all about. The question is really, is this smoothed pressure response, perceptually the best way to go. There may be some dissent there.
For HT boom bang stuff, I'd say yes. For stereo, the OPs subject, I'd say no, at least not above 40hz. One can always decide for themselves what fits their needs for reproduction best.
This whole site is worth reading, start here.
As is this one, starting with Soundfields vs. Human Hearing and A Low-Complexity, Fast-acquiring Perceptually Tuned Room Correction Algorithm (can't direct link PPTs).

cheers,

AJ
Loudspeaker manufacturer