More Power or use subwoofer to boost bass for music


Hi,   just want to know if anyone can offer their opinions on how to boost the bass when listening to 2 channel music.

I just got a pair of B&W 804 D3 and would like to get more bass out of the speakers.   I remember the bass was pretty punchy when I heard it in the dealer showroom, but I don't seem to get that in my setup.   I currently have Parasound A31 power amp with 250 watts per channel.

So the question is whether I should get a more power amp, or add subwoofer to my 2 channel music.  I'm a little bit of a purist and would prefer not to use a subwoofer for music, but I'm open to this option.

I would definitely appreciate if anyone can share their experience/opinion.   Thanks very much.
128x128xcool
I remember the bass was pretty punchy when I heard it in the dealer showroom, but I don’t seem to get that in my setup.


While I love subwoofers, room acoustics are a better place to look first.

The key part of your description here is that you say they sounded great in the showroom, which was probably better treated.

Why don’t you give GIK acoustics a call, and in particular ask about their soffit traps?

Do your room first, then you’ll be in a much better place to evaluate.

Best,

E
Try to put the speakers closer to a wall or corner. You should see an improvement in bass.
Thanks.  I'll take a look at GIK acoustics.  I've always been intrigued by the idea of room treatment, and know very little about it.   Also, I think my options might be limited.   My listening area is near a stretch of windows with no curtains, just shades.   I always think there's very little to do about it unless I put up thick curtains, but I'm not willing to do that.   I just need to strike a balance, I supposed.

BTW, what are bass traps?  Are they for enhancing the bass, or calming down the excess bass?

Thanks.
Sorry xcool, you are new and have no way of knowing the answer to every question is GIK. Even though you specifically want more bass, and everything GIK makes can only absorb bass and never enhance it, still the answer is GIK. Or EQ. Surprised he didn't say EQ. Maybe saving for later?

koestner is right. First step is always speaker placement. Closer to the walls, either front or side, will have a big effect on bass response. Also your listening position. But the walls also reflect higher frequencies as well and so if the speakers are closer than about 3 feet to a side wall the reflections begin to interfere with good imaging. So its a balance and a trade off.

You may be a minimalist, and so am I. More power won't work. One sub won't work. GIK will improve everything and your bass will have greater definition but by absorbing not enhancing. When it comes to bass the fact of the matter is the minimalist approach is four subs. Check it out. https://systems.audiogon.com/systems/8367 Read the reviews, do a search, read about DBA. 
OP you are new and don’t yet understand that the answer is 4 or more subs in a forest of box’s and wires placed quasi randomly about your room.

bass is a wide topic and for most music listeners spans from 30 HZ to the power range of 200-250 HZ. You might try to recall or ask the dealer where those speakers were placed in the demo from side and back wall. IF you do have to compromise with near surface ( back and or side wall ) coupling, then GIK or another brand of broad band absorber panel or three to address reflections will help w imaging. Finally also you might need to tweak your listening position a bit. Room modes effect. Bass , especially below 120 HZ... even a few feet can matter.

there are other ways to add great subwoofers if Indeed the problem lies below 100 HZ. One has built in EQ.

and yes, swarm aka multiple subs...works if the crossover frequency is low enough and you like the clutter.
Also IF flat frequency response in room was the only measure of bass quality why are there a plethora of bass guitars, standup bass, etc out there....?

this from a bass player of LiL reknown....

Someone should tell millercarbon to stop adding a link to every post he submits. One look at that room would send most running from the multiple sub approach.
To enhance bass you need to try to position the speakers closer to walls to amplify the lower bass, or add subwoofers. The answer is not adding multiple subs or adding bass absorption. The rational approach is to start with proper imaging using a method such as The Master Set. Imaging is key to proper sound from a stereo source. Once the imaging is perfect you can then add subwoofers for the lowest frequencies if you want more bass. It may help to use a computer and microphone to real time analyze the frequencies in your room. Then you will know how far down your speakers go. If you want 20 Hz or below you will need subwoofers. They are tricky but to get 20 Hz and below you have to move air. Lots of air. You will need 15” woofers. The idea of a “swarm” of subs is based on evening out the nodes. It’s an admirable goal but rarely practical. One well placed sub is good but not easy or perfect. Two well placed subs are better but beyond that you are spending a lot to get a little. Like horsepower. Look up Harman Kardon white paper on sub placement. Seminal work. Proper placement of stereo speakers doesn’t necessarily mean the proper placement for bass or subs. I recommend Hsu Research or SVS for affordable well made subs. That way You can afford two or three. Hsu sells pairs of identical subs. Best of luck and keep us posted. 
Hello cool,

     Millercarbon is correct, a 4-sub distributed bass array (DBA) will provide excellent bass performance throughout your entire room and integrate seamlessly with your main B&W speakers.
     If you’re only concerned with attaining excellent bass performance at a single designated listening seat, however, using 2 good quality subs will will work about just as well as a 4-sub DBA.  You may even be able to attain very good bass performance at a single listening seat with a single higher quality, and more expensive, sub that comes with a mic and has room correction software.   You would first optimally position the single sub in your room using the crawl method (you can google it) and then utilize the room correction function to fine tune the results.
     2 subs, even if they’re smaller and less expensive, will generally perform about twice as a single sub, even if it’s larger and more expensive. The benefits of using 2 subs are increased bass power and dynamics when the music calls for it, neither sub is operating near its limits and the bass will be better integrated with your main speakers.     Whatever sub or subs you decide to use, it’s very important that each sub has separate controls for Volume, crossover frequency and continuously variable phase.  These controls are critically important for adjusting them optimally to your room and system.  It’s also beneficial for the subs to have the choice of inputs, rca line level and high level speaker wire.       You’ll also notice an improved soundstage and improved midrange and treble performance of your main speakers utilizing 2 subs.
     I suggest trying a pair of SVS SB-1000 subs or similar Hsu subs for about $1,000/pair.

Good luck,
    Tim
xcool OP

The combined impedance and -phase angle graph shows these 804’s are a hard load in the bass from 60hz to 150hz where all the power is needed
https://www.stereophile.com/images/913B804fig1.jpg
Yet the frequency response shows that they have a slight rise in that area, and should give big bass if driven well. https://www.stereophile.com/images/913B804fig4.jpg

The second page of the Stereophile review often complains about the lack of bass from the 804 D’s. And looking at what they drive them with, it was the same amp as you a 3 channel HT Parasound A31 that has trouble doulbing wattage from 8 to 4ohms, let alone down to 2ohms
https://www.stereophile.com/content/bowers-amp-wilkins-804-diamond-loudspeaker-page-2

I think your amp just like the reviewers, is not up to driving the bass with good current delivery, try something that can, and you then won’t need any subwoofers and the problems they bring to seamlessly blend in to the mains.

Cheers George
Thanks George.   Thanks for the information on Parasound A31.   That is good to know.   Maybe I do need more power to drive those B&W.   I'll checkout the review.

Also, many thanks to others for information on room treatment and multiple subwoofers.    One thing I should have mentioned in my original post, is that I live in an apartment, not small, but average size.  I don't have a lot of options to accommodate multiple subwoofers.   I actually do have a subwoofer now.  It's a very old Def Tech subwoofer from the 90's.   It doesn't have a whole lot of connection options.   I only use it for movies.  I was looking to replace that anyway.   

I do like the option of adding some acoustic panels, and will look into that further.

Thanks!
xcool OP Just found proper test on the A31 as I thought not much current ability into low impedances. The 4ohm wattage should be a lot higher, and they didn’t do the 2ohm as it would have been trouble (bang maybe). Not the amp for these speakers.

 Cheers George

BHK Labs Measurements: Parasound Halo A31 Three-Channel Amplifier
  • 1% THD 232.8W @ 8 ohms, 352.0W @ 4 ohms
  • 10%THD 285.0W @ 8 ohms, 422.9W @ 4 ohms

dual subs; as large and powerful as you can fit and afford. I like the big HSU Research units
i don't remember what the dealer use.  It was actually in Magnolia shop of Best Buy when I heard them for the first time.  I think they might just be using a Rotel integrated.
Any particular reason you went with the A31 vs the A21/A21+ or even JC5? While a swarm might be one of the options for big low end, often they are impractical space/position wise and still require proper setup to get right. So reality is, any sub setup will require proper placement and dialing in. You might be better off to try the above first, room treatment, speaker placement etc. These are all things that need to be done anyway if a sub/subs are part of the picture. Also, cabling can make a big difference as well, power particularly as well as the rest. 
Reason for A31 is because I only run a 3 channel (L,R,C) home theater.   I don't have room for surround speakers.   I have the Marantiz 8802A preprocessor for both movies and music (via Pure Direct mode).    I'm also looking for a stereo pre-amp right now.  I'm considering Parasound JC-2 or Mcintosh C49.  I actually had another post in this forum about that.
Sometimes amps are the problem, if you can get a loaner, go for it. If that doesn't help you dramatically, look to the room.
I worked at Magnolia for a bit, and their standard setup had the 804s positioned very close to the back wall so maybe not surprising you remember hearing more punch when you were there (I used to pull them 4’ out into the room where they sounded much better albeit with less bass emphasis). Regardless, 804s have never had prodigious bass output and could certainly benefit from at least one good sub. As @noble100 mentioned, the improvements extend beyond bass to expanding the soundstage and overall image palpability. I’ll never forget the first time I heard a good system with properly dialed in subs. Of course there was the expected bass depth and impact, but when he disengaged the subs the entire soundstage collapsed and the sound overall went limp. You can certainly achieve better sound with room treatments and EQ, but there’s really no substitute for what good and well-integrated subs can do. I like the suggestion of a pair of SVS SB1000s that run $950 and offer a generous in-home trial period, but I seriously doubt you’d be returning them.

One last thought — if your speakers are new and don’t have at least 100 hours of quality playtime on them you may not yet be hearing all that the 804s have to offer.  In any event, best of luck.
The idea of a “swarm” of subs is based on evening out the nodes. It’s an admirable goal but rarely practical.
This statement is false. A distributed bass array such as the Swarm is far more effective at getting the bass right in a room than room correction or bass traps; its a more elegant approach.


This isn't to say that using bass traps and room correction won't help, but if you have a standing wave in the room (which can be a reason why a single sub or pair of subs don't seem to make much bass despite having plenty of power and the bandwidth needed) all the room correction will do is make the amps make more power at the frequency of the standing wave cancellation. No amount of power will solve a standing wave, since the energy is being cancelled.


Bass traps don't intelligently work at the frequency needed to prevent the standing wave (which is the result of the bass waveform bouncing off of the wall behind the listener and cancelling itself at the listening position)- they work at all bass frequencies.


Now if you combine all three then you can get spectacular results.
Jesus, the 4 sub cult is strong here.
Just physics. Cults, to my knowledge aren't bassed (see what I did there?) on physics.


IMO its fairly easy to set up a set of Swarms in a smaller room and keep it neat, since the Swarms are designed to work placed against the walls and also work best if the placement is asymmetrical.


Of course you can get good bass with only one sub, but it has to be placed in exactly the right location, which (more often than not) may not be the most convenient.

Vandersteen = 11 bands of EQ with more cut than boost with EQ centers set on typical room nodes not typical 1/3 octave bands... some science cult thinking at work there... since 1977 and still going strong and I might add a supporter of swarm IF done correctly so as not to muck of the stereo image...
But since statistics is science, let’s consider the “odds “ of getting 4  or as some would say 5 objects placed in a convenient location vs. one....

having a bit of fun Ralph, you are a true warrior for the science and the music
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In an attempt to be helpful to the OP I want to present the research data from Harman regarding multiple subs. The research is extensive with computer modeling and multiple variations in numbers and placement. It’s easy find online and well worth the reading. Multiple subs are not a cult but are scientifically proven to even out bass nodes but are they really necessary?  Where do you want to spend your limited funds?  Here is their conclusion:
” Four subwoofers are enough to get the best results of any configuration tried. Two subwoofers is very nearly as good and has very good low frequency support as well.”

The midrange is where most of the fidelity in reproduced recordings lies, in my opinion. Proper speaker positioning and an excellent midrange would be my first goal. If money is left over considering amplification, room treatments, cabling and two matched subs, then get two more. But as their research shows you can do very well with two high quality matched subs. 
The OP: I have 2 speakers and I’d like a little more bass, closer to what was in the showroom.

The cult: Your problem is you have 1/3 the number of speakers you need!! You must add 4 more, bring it up to six!!!

Are any of you listening to yourselves?? Really??
But since statistics is science, let’s consider the “odds “ of getting 4  or as some would say 5 objects placed in a convenient location vs. one....
:)  


Of course, the science shows that multiple subs don't have to be placed perfectly for them to do the job much better...
Are any of you listening to yourselves?? Really??
Yes, we non-cult-DBA-knowers are- however you might want to take a dive into the research. Put another way, you know how you are sounding right now??
Start with 1 sub: 2 would be better: REL, Martin-Logan or JL would be great options. Doing a more powerful amp may lead to frustration. The subs will give you more flexibility and adjustments to compensate for room variations.
Ralph :

 I have nothing against 4 subs. They are technically a good idea.

What I have a problem with is the cult that they are the one thing that should be discussed when a poster asks for help with a little more bass.

That is the cult. 

It's like some one who won't go to the store to buy a bag of rice because all they have is a Mercedes and the Ferrari is in the shop.
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I would start with a better amp and attention to placement. Regardless of power specs I think they deserve a better amp. After that I would consider sub(s). A pair of 6.5 inch drivers in a relatively small cabinet can only put out so much real bass at real volume out to the listening position.
Eric, as the OP has a set of speakers that retail(ed) for about $8-10K USD, I think it is fair that true quality is his goal. He is also in an apartment, so you really want to avoid modes as that can increase the noise transfer to your neighbors and limit how much bass you can practically get.


Yeah, and you just made the argument for bass traps and room treatment.  Thank you.

Erik
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Their room is set up for best sound!

 Get a average sub and enjoy.
no need to spend a lot.

 Newegg has An Energy sub for 112$ this weekend.
great sub, better price!

Cheers George

BHK Labs Measurements: Parasound Halo A31 Three-Channel Amplifier
  • 1% THD 232.8W @ 8 ohms, 352.0W @ 4 ohms
  • 10%THD 285.0W @ 8 ohms, 422.9W @ 4 ohms


heaudio
This is a misinterpretation of how an amplifier will behave or at least an interpretation without adequate knowledge.

Once again it’s you that has the inadequate knowledge sunshine, those wattage figures from 8ohm to 4ohm clearly show a lack of good current delivery in this amp especially even though it’s not shown for obvious reasons down to 2ohm where these speakers need power.
I already had made an argument for them. However in an apartment a bass array has far more chance of a successful implementation and likely less obtrusive.

Uh huh..... yeah, we have nothing at all but space in an apartment, space and money for 4 subs, and the wiring.... yeah, lots of that.

Or, as my experience and measurements have shown, you treat the room with some decent bass traps and wall coverings to ensure the treble/bass balance is correct but no.... that's too much ....???


Hahahha.  Cult.
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The swarm was an interesting idea which is promoted by fetishists whose motives and honesty I question.

The truth is many modest systems achieved great bass with proper speaker placement, modest acoustics, and soemtimes a sub with an EQ long before the swarm and there will still be systems with great bass long after the swarm.

To hear the fanatics tell it, no one has even heard bass before them, and only they can fix it. Also, only they know about room acoustics.  It's magic.  Ignore all the previous work that has gone before, because it's bunk before the swarm.

Please mark me down as some one who no longer believes those people are well meaning.  I'll no longer bother arguing with anyone of that ilk. You have convinced me of your intension$$$$$$$$$$$$.
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@erik_squires wrote:

"The swarm was an interesting idea which is promoted by fetishists whose motives and honesty I question...

Please mark me down as some one who no longer believes those people are well meaning. I’ll no longer bother arguing with anyone of that ilk. You have convinced me of your intension$$$$$$$$$$$$."

For the record, NOBODY here has a financial interest in the Swarm except for me.

Erik if you feel that the main fetishist behind the Swarm needs to have his motives and honesty questioned, I’d like to hear you out.

* * * *

Xcool, I apologize for entering your thread to squabble with someone. Erik and I are not enemies (far as I know), but we do have differences of opinion on some subjects (that NEVER happens among audiophiles, right??). Imo bass traps (absorbers) are not the solution when you’re trying to increase the net in-room bass energy, but I am absolutely a fan of GIK Acoustics.

Anyway let me try to offer some thoughts about your bass situation, taking into account that four small subs probably isn’t feasible:

Your B&W’s gently roll off by about 4 dB per octave from 100 Hz down to 30 Hz before boundary reinforcement according to Stereophile’s measurements, with the rolloff accelerating rapidly below 30 Hz. In rooms with generous boundary reinforcement, this can give bass extension down to 30 Hz ballpark.

Presumably your room does not provide generous boundary reinforcement at your listening position with the speaker positioning you have. Just for fun, you might try standing at the wall in the back of the room to see how the bass sounds there.

You asked about amp or sub. I am inclined to think that sub(s) will make a bigger difference, and a more fine-tuneable one. I was a Parasound dealer for many years and think your B&W’s are well within your amp’s comfort zone.

You might consider this: Adding two smallish subs, one along a side wall (but not centered), and another along the rear wall (again, not centered). Considering your B&W’s to be bass sources down to 30 Hz, this would give you four in-room bass sources, with two of them (your B&W’s) symmetrical with respect to one another, and the other two asymmetrically placed. I can explain why this might be beneficial if you would like.

I see now that this suggestion is pretty much a repeat of heaudio123’s post above. Nice job, heaudio123.

Xcool, best of luck with your quest.

Duke
Grand Poobah of the Swarm Fetish Cult
Hey @audiokinesis thanks a lot for your suggestion, and also everyone else for such a colorful discussion.   :-)  

There are a lot of good information here.  One thing for sure though is I don't have the space for 4+ subs.    I definitely have space for one sub.  That is to replace my old one that I only use for movie right now.   It's sitting in the corner of my room, but partially obstructed by piece of furniture about 1 foot in front of it.   So the location is not ideal.   It will be a challenge for me to try to fit a 2nd sub in the room.   BTW, my speakers are already very close to the back wall - right around 1 foot away.    So technically, I'm already placing my speakers at a good location from the bass perspective.

Anyway,  I think I might give a new sub with EQ a try, and get myself out of this 'purist' mode :-).   Will also do some research on room treatment.   

Actually I might start with a new dedicated stereo preamp for my 2 channel music and work from there.   

There are definitely a lot of moving parts in this hobby, and a lot of trial and error to pursue the best sound.  But it's all fun stuff.  :-) 
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Well unless someone here is interested in a professionally designed sound system, complete with 3D modelling of the acoustic field based on architectural drawings, industry measured material properties, and sufficient speaker models or they are trying to design tolerable audio into the latest miniscule consumer gadget and need to design and model the acoustic performance before finalizing the design and committing to tooling, or they need help with designing and implementing psychoacoustic experiments, or, and this would be unlikely, they need a device for medical or industrial "sonic" treatment (or measurement) then yes, I would be guilty about my motives. This is not the case, here.


The swarm was an interesting idea which is promoted by fetishists whose motives and honesty I question.

The truth is many modest systems achieved great bass with proper speaker placement, modest acoustics, and soemtimes a sub with an EQ long before the swarm and there will still be systems with great bass long after the swarm.

To hear the fanatics tell it, no one has even heard bass before them, and only they can fix it. Also, only they know about room acoustics. It's magic. Ignore all the previous work that has gone before, because it's bunk before the swarm.

thanks for that @audiokinesis
Duke..when using 2 subs with floor standers, do they need to be identical or can they be close models...Could i use a REL S/3 with my REL S/5 ? thanks...I also have no room for 4

heaudio123
"No "sunshine", all the numbers show is that it can deliver 350 watts approx into 4 ohms with 1% distortion. Those numbers do not show output impedance which is what would actually jmpact frequency response"

As has already been sufficiently, properly, and correctly explained you are once again completely wrong even though you are partly correct but being partly correct is not fully correct. Output impedance is only one factor in this equation which you have sought to oversimplify by overlooking others factors as has been duly noted to you hear by others you’re pretending to be some kind of electronics/audio/acoustics "expert" suggests based on you’re own summation that you "perhaps" once worked for Radio Shack and are now qualified to call your self a "conskltant" even though you have such incomplete understanding of basic, rudimentary, fundamental elements involving audio and Music Reproduction Systems.
@jl35 wrote: "when using 2 subs with floor standers, do they need to be identical or can they be close models..."  

They do not need to be the same. 

Duke