Do you think you need a subwoofer?


Why almost any one needs subwoofers in their audio systems?

I talk with my audio friends about and each one give me different answers, from: I don't need it, to : I love that.

Some of you use subwoofers and many do in the speakers forum and everywhere.

The question is: why we need subwoofers ? or don't?

My experience tell me that this subwoofers subject is a critical point in the music/sound reproduction in home audio systems.

What do you think?
Ag insider logo xs@2xrauliruegas
Raul: Why do you think there is so much resistance on this subject? (Pun intended.)

Audiophiles are normally willing to go to any length to improve their system in even a small way, but for some reason the mere mention of subwoofers is enough to make them put their hands over their ears and just say no.

Certainly you have done your best to change people's perspective on this issue.

It's an interesting psychological question.
Dear Jimjoyce25: There are many factors that contribute to develop a poor " image " on subwoofers specially in the high-end stereo music reproduction market.

If you remember in the past ( many years ago ) no one use subs, the speakers were designed with a low bass range down to 35-40 Hz in the " biggest " models, almost no one ( for home music reproduction ) made speakers designs with that additional 1.5 octave on the low bass ( there were some exeptions, my ADS ones are one of that exceptions, but not many. ). Many manufacturers perhaps decide that because a " normal " speaker that goes down ( flt-clean ) to 20Hz must be BIG ( difficult to have at home ) and expensive and maybe they think that there are no " music " down there.
This last subject were and still today are supported by reviewers and audio dealers that are whom give the advise to the customers, so they give a non correct information to us the customers, so we have a misunderstood on the subs subject.

But not only that, in those times when the people start to ask/use subs normaly they use one unit ( stnd alone where you need to buy an amplifier to power it. Not many self powered subs in those times. ) and only to re-inforce the bass in their systems but with out any know-how or the right advise to why and how to do it ( some models even came with a fixed low-pass frequency and with out almost any facilities to really " blend " with your system. ), as time goes on many of these sub's users came disatisfied with the subs and put on sale and in their minds the figure of a subs were a " bad move " and they pass their experiences on the subject to other people.
If you check on audio magazines ( any ) of those times I can't remember any single reviewer that owned subs in his systems even the subs magazines reviewes were almost none, so the for the customers the subs were nothing or a " must " to have

Unfortunately the commercial subs came with no-facilities in the crossover, many with out amplifier, not so good drivers/woofers, not so good electronics ( even today some sub manufacturer IMHO don't put interest in the quality needs on the subs. That's why some of us made mods on them. ) and with almost no advise from any one. These anomalies make that many times the subs sound reproduction were of bad quality: only one note bam or boom boom and nothing more to appreciate.

The audio industry grow-up: better recordings, better quality speakers, better quality electronics and the like. The subs grow-up too but not at the same quality level than the other items and the audio magazines and audio dealers still with out support the subs subject, mainly IMHO because a very poor/small know-how about. So how the customers can think on the subs if no one speak about its advantages like a good alternative to improve the quality performance of almost any audio system? even the speaker manufacturers that build subs like Wilson, Krell, Thiel,, etc, etc, don't really promote their subs models, why? I can't be sure if it is for they do not have the know-how level or because they have it and goes against its full business, let me explain this last comment with an example:
if someone owns a WattP-8 and want to improve/up-grade the quality performance on his system through a new speakers ( normaly same manufacturer, in this case Wilson. ) almost always he/they think in the next top model: the MAXX3 instead to add subs to the WP8, this subs alternative it is not only less expensive but one that beats the MAXX3 quality performance but the manufacturer and the dealer say nothing about, never give to the customer this alternative.

There are a lot of mis-information , misunderstood and non know-how on the subs great alternative in a stereo systems. Many people are still thinking that the subs are for HTS and not to listen " serious music " ( even manufacturers like REL that have not a high-pass filter in its crossover. ). Unfortunately is sad that all these people are loosing the best an ever opportunity to really improve the quality performance in their home systems.

In this thread we can read many of the advantages adding two subs in real stereo fashion where the main one is not IMHO " only " to achieve low bass but improve the quality performance of the main speakers!, till the people understand the why's and how's on the subs subject they will continue hearing ( obviously not all. ) home systems with a " weak " leg.

Yes, IMHO everywhere ( manufacturers, reviewers, dealers. Not all. ) non know-how on the subject is the main " culprit ", of course that money or space/place's limitations have a role too.

Like everything the subs subject is an educational one, many audio people are at the low subs learning curve, sooner or latter we all will grow-up on that learning curve where the rewards are almost incredible and of paramount importance in favor of the MUSIC perception.

There are other factors that have influence but it will be too long to analyze each one even I can be wrong on what I think.

What do you think? do you want to grow-up? do you want to be better?

Regards and enjoy the music.
Raul.
Hi Raul, I'm late arriving at this party and have not read through all seven pages of discussion. Therefore, forgive me if I repeat something already covered, but I'll throw out a couple of thoughts into the mix.

First, I've been told that the mid-point of the acoustical energy of a symphony orchestra (obviously on average) occurs around 220 to 280 Hz (depends on who you ask). Think of the implication for a two-way speaker system with a crossover between 1500 and 2K Hz. That poor mid/woofer is being ask to produce nearly all of the energy. Even a three-way system with a 300 to 500 crossover, that woofer has a load. Notice I'm talking about acoustic energy here, not frequency response, so think about the requirements on the woofer and amp driving it in those terms.

Related to this is the situation where the lower the frequency, the more energy needed to drive it to a given reference level. For me it becomes easier to understand why a separate, powered subwoofer(s) covering the first or first and second octaves can be so beneficial.

Which brings me to my second thought. Many years ago I visited a very well respected dealer for a subwoofer demo. I no longer remember the sub model but the prime speakers were Spendor BC-1s. Rather than the expected organ works, bass driven rock, or synthesizer demo, the owner played a solo cello recording. As he switched the subwoofer in and out, the difference was heard immediately. It was not the low bass extension but the improved clarity, depth, and spaciousness that was apparent with the subwoofers switched in. Even if it would not seem like a cello would tax a woofer and amp, removing the lowest bass (wish I remembered the crossover point) responsibility from the regular woofer and amp cleaned up the sound far more than I would have ever expected.

Food for thought.
Dear pryso: Thank you to share your experiences about are really lightining.

Yes, IMHO the main advantage in the subs integration to almost any audio system is to lower the IMD making improvements like the ones you experienced.

Yes, through these seven tread pages in one way or the other the people that participate cover several subs advantages like the one you name it and you can read here something else about:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1117893153&openflup&27&4#27

Regards and enjoy the music.
Raul.
Lord no the 7in woofers on my Thiels go plenty enough deep for an apartment. Eventually though when I have everything entertainment wise in the same room and go for surround the smart subs will be tempting.
Dear Velocityyofhue: As I posted and from my point of view and experiences the main target to add subs to your audio system ( almost any system ) is not to go deep in the bass or higher bass quantity but to improve the quality performance of your Thiels ( and achieve a lot whole better system performance. ) lowering its high IMD/THD ( intermodulation distortion/total harmonic distortion. ), this target when you achieve it makes a difference like night and day, period.

Now, your Thiel's are a very good example on the subs subject because the Thiel woofer handle a wide ( more than five octaves ) frequency range: 28-30Hz to 1Khz ( due to its first order slope crossover. ).
That woofer needs to reproduce at the same time a 40Hz frequency and a 500Hz one ( example, the reality is more complicated due that the woofer has to handle all the frequencies in its very wide range. ) where the needs to the 40Hz frequency reproduction stress ( IMD ) heavy the 500Hz frequency reproduction where this one loose its un-distorted/clean reproduction that we heard like a smeared non-transparent no precise definition, etc, etc.
I know that you like what you are hearing, well you can't imagine how good is your system till you make that the IMD in your speakers goes really lower and one of the alternatives is through the integration in true stereo fashion of two self powered subs blended seamless.

When you achieve this the Thiel's woofer will work between around 80 Hz and up lowering the IMD that clean-up all the frequency spectrum response, now that woofer will work with out the " stress " ( excursion, overhang and the like that affect seriously the whole woofer quality performance: a heavy compromise. ) in favor of overall speaker quality performance.
At the same time the whole bass response will improve its quality performance because right now that bass frequency range is handle for a dedicated ( was expressely designed for ) speaker ( the subs. ) and for a dedicated amplifiers that was expressely designed to match exactly the needs of that subs drivers.
Here you will have and wll hear the quality on the bass that you never heard in any full range speakers ( non powered ) at any price.
You not only improve the quality of the bass response but obviously you improve to in the bass quantity and in a lower/deep bass response that you will hear only when the recording demand it.

Everything change for the better: power handling because your Krell will be working in a less wider frequency range: its overall performance improve, sounstage will be a lot better too, there are so many improvements that is almost impossible to name it.
Other thing: right now the position of your speakers is a compromise between the in room bass response and the mid/high response, there is a trade-off.
When the " deep " bass liberate the Thiels then you can move it/change a little its room position to achieve a better in room mid/high frequency range response/perception and the subs will be locate too at its best in room position: best of two " worlds "!

IMHO it is worth to try it, the change is of paramount importance with several and true rewards.

It is almost useful/vain to argument against the subs with out listen/try the whole alternative.

Of course that some speaker manufacturers and/or audio dealers/reviewers can't support the subs " road " because the alternative goes against business ( $$$$ ) where the money is on sales of bigger ( more costly ) ( next model in a speaker line. ) or different speakers ( more expensive )than in two inexpensive subs that we even can buy second hand.
But even IMHO if we are wealthy enough the fact is that we can't achieve better quality performance ( everything the same or that the main speakers were decent speakers. ) with the new " big " speakers " than with the un-expensive subs alternative.

Regards and enjoy the music.
Raul.
Big speakers need love to Raul.
Look at Oneobgyn. He's got he big Wilson's and the big JL Gothams. I bet there is unbelievable ease to his system.
Gregadd
Dear gregadd: That system is a " impressive " cost no object alternative.

However, those Gothan's are used as a bass re-inforce " tool " where the Alexandria's works full range.

Here, the owner's system choose ( IMHO with all respect I take this system example like that an example only and not like a critic on it and not telling that my " voice " is the only and right one. ) not taking advantage on the subs whole subject ( well he is taking advantage on the bass re-inforce but with many trade-offs, one of them is that the main speakers are playing in the low bass at the same time than the subs. ).

I f I was " there " ( unfortunately I did not, a healthy " envy ". ) my choice will be for the Velodyne's DD-15/18 or the DD-1812, both have a high-pass filter that we need to liberate the Alexandria for the low bass range.

The Velodyne choice not only give me that HPF but better specs on bass frequency range and its HD is the lowest on commercial home subs: less than 0.5%, this is very important because we want a clean in room response down there and according with the HD " quality " of the main speakers.

Other advantage to separate the low bass on the Alexandria's is that those Lamm's amplifiers will perform better with out " see " that bass range.

The Alexandria's are " easy " to handle almost for any amplifier SS/tube due to its very high efficiency ( 95db. ), Wilson say that you can start with amplifiers that put at least 7 watts but IMHO and due to its low impedance ( 3 ohms. ) and complex electrical impedance curve this speaker is not an " easy " one and its needs ( like the music needs specially on transients. ) are demanding to a matched amplifier ( not almost any. ) to show its best and great quality performance.

The sub's integration in true stereo fashion IMHO can help to improve the quality performance of the Alexandria/Lamm combo.
Of course that I can be wrong but this is what I think about and what I do with that system.

Gregadd, the audio/music home sound reproduction is a very complex one if we want to achieve a near " perfect " quality performance. The audio chain has many links and the relationship between those links are almost infinite.

IMHO each of those links has its own learning curve where we have to understand the differents steps in that learning curve to take its advantages and try to eliminate its dis-advantages. This link/chain " learning curve " know-how is one of the keys to our " audio dream " sound reproduction.

The sub's subject is one of those links where many of us are at the begin/start of the sub's learning curve, we need to grow-up ( like in other audio link's learning curves. ) learning with true experiences about, it is very difficult to learn if we don't " live "/feel with experiences on the subject.

IMHO as we grow-up on each audio link " learning curve " as better ( not only different but better. ) quality performance will show our home audio system.

Regards and enjoy the music.
Raul.
As usual Raul you are not without an good opinion. Dragging us kicking and screaming to better sound.

My point was just because you have a big expensive full range speaker does not mean you don't need subs.
As for what the crossover point should be and whether Jl or Velodyne is the proper sub I'll leave that fight between you and the Doc. I'm in enough controversy.
Gregadd
The sub's alternative IMHO is a tremendous " tool " to improve almost any home audio system quality performance that use tube amplifiers.

Due to tube technology characteristics and the fact that in a sub's system the amplifier does not " see " bass frequency range this improve the tube amplifier overall " power " in the remaining frequency range ( main speakers ) and permit that this un-stressed tube amplifier performs and match better to the main speakers.
The quality improvement is really significant and IMHO this " road " is a must to go specially when we are using tube amplifiers, I can't imagine a better system up-grade everything the same.

Regards and enjoy the music.
Raul.
Dear Gregadd: No fight, I respect that great system owner: it is only that maybe there is a tiny " room " to improve. Always is a temptation try to help, no critic at all.

Regards and enjoy the music.
Raul.
Raul:

I agree with your basic thesis about using stereo pairs of subwoofer for improved performance in virtually all sonic categories. I note that you are proposing using a high pass filter to prevent the bass drivers from handling the lower frequencies. In fact, you are suggesting this approach even for such stellar bass producers like the Wilson Alexandria. I prefer a slightly different approach: I would characterize it as “low bass augmentation”. In my system, I am running the Magnepan 3.5 full range. In my room the Maggies are down about 3dB at about 30Hz. I am running a stereo pair Sunfire Signature subwoofers with x-over point about 30 Hz. The slope and phase are adjusted to ear. I have been able to obtain seamless blending among the Maggies and the subwoofers.

I did not want to use the high-pass filter in the subwoofer because I felt that any gain in freeing up the Maggies from handling the bass frequencies would be offset by the added distortion or corruption of the signal due to the additional filtering. In fact, I experimented with both scenarios and preferred running the main speakers full range. The sound was less mechanical sounding.
Dear Gmorris: As you point out a different sub's integration with different trade-offs ( advantages/dis-advantages ).

I prefer to lower the IMD on the main speakers in favor of an improve in the quality performance on the main speakers and to handle the low bass with a dedicated speaker ( sub s) that was designed in specific to that frequency range along its self-powered amplifier.
IMHO no full range passive speaker ( like the great Alxandria's. ) can show/even the quality performance in the bass range like a dedicated self powered sub, the right sub and at the same time I don't know any amplifier ( SS/tube/hybrid. ) that can even the matching between the driver ( woofer ) and the amplifier in the sub's that was designed to the specific needs of that woofer for that specific frequency bass range, synergy is the name of the game.

The key is the quality of the crossover that in Velodyne, Revel, and the like are very " decent ".
The ideal " key " is to make directly the crossover high-pass filter at the main ( internally ) speaker amplifier(s) and if you can't do it then through the sub's own crossover.

The choice of the sub's model is a critical subject, not all the sub's are the same and not all the sub's have the same quality performance and the same quality " self " electronics specially its crossover.

I prefer too the use of the same amplifier in the main speakers, the right amplifier.

When we use two different amplifiers ( like in your system ) IMHO we have two different performances due to the diferences between these two amplifiers: different output impedance, different frequency response, different THD, different gain, different slew rate, different colorations,...different noise level,....different.....diferent..., etc, etc, the only and almost the one similarity between both units is its name: amplifier.
I know that you like it and this is the important factor because is you who are living each day with that system.

I respect your approach, however the targets and its quality level that you achieve are totally different from the targets and quality levels that we achieve trough the alternative that I support.

Regards and enjoy the music.
Raul.
"...Maggies are down about 3dB at about 30Hz..."

So why xover @30 hz. That gives you suck out in that region.
if you plot a curve most speakers neither drop of a cliff nor jump on the cliff.
At some point they began to roll off. Especially if you are talking about a xover. So they will start to roll off at say 60hz. There would be a decreasing slope all the way to 30 hz. The subs xover in my opinion should kick in @ 60hz and slowly rise to where it takes over completely. A brick wall approach either means the sub kicks in to early or too late. From the response curves I've seen, this is a better approach.
When I used The CLS they were 3db down at about 40hz. Sometime it is difficult to tell because manufacturers don't tell the truth. With exception of Stereophile, reviewers don't measure. Too make matters worse measurements are done in anechoic chamber which can't measure the response in your room. Thus the nonadjustable xover point of the Janis was 100 hz. Most of the xocer slopes are in the 6db/octave,12db/octave or 18db/octave. 6 being considered very gentle with 18 being very steep. It depends on the design philosophy of you speaker.

if you check the Stereophile review of your speaker there is probably an example of the xover and how it rolls off. I admire those who can adjust speakers by ear. I bet that using a spectrum analyzer in yuor room reveal they are not exactly right.
Gregadd
Dear Gregadd: From the planar speakers the Maggies are one that I like it, I had the opportunity to heard he 3.6 in my system ( years ago ) due that the dealer here was a close friend of mine and in a friend's system the 20.1, very good ones.

Yes, certainly I have " anomalies " in the frequency response spectrum on my speakers/room, however I can tell you that our ears ( yours, mine and everyone. ) along our know-how/experience are very good, sensitive and discriminate tools on sound reproduction perception.

Almost all different sub's approaches are valid , this depend of what targets do you want to achieve and what quality level do you prefer.

Regards and enjoy the music.
Raul.
The aerial sw-12 takes a correct approach. While not cheap (approximately $10k)offers a variety of slopes up to 24 db/octave. It is flat to at least 2Hz and allows a maximum cut in of 100Hz. Thus it will mate well with mini-monitors.It also offers a variety of beautiful finishes for those who are turned off by black cubes. If you like black, you can get that too.
gregadd
Dear Gregadd: Yes the Aerial is very good option. Its price was a little to much for me but its quality performance is really good.

MK the designer/owner of Aerial was/is the one that made the design of my ADS main speakers.

Regards and enjoy the music.
Raul.
Raul---What is your view of the method used in the Legacy Focus: Including separate subwoofer drivers in the same box as the tweeter, midrange and regular woofers, and bi-amping with a crossover.

In this way, (i) the stress of reproducing low bass sound is removed from the woofers, and (ii) separate amplification is provided for the subwoofers.

In this way, separation is achieved without the cost of an additional box.

Is there any downside to this approach?
Dear Jim: THis Legay is a very nice approach/design that address the IMD subject between other things.

Downside?, well nothing is perfect: if I was Legacy I will make those bass drivers self powered with a dedicate amplifier that match exactly the drivers needs and take care in deep about isolation between those bass drivers and the whole speaker.

I never have the opportunity to hear the speaker but seems very good and has very good reviews.

Regards and enjoy the music.
Raul.
Dear Jim: Other factor that could help to that Legacy speakers is to separate the subs from the main box.
Anyway it looks like a very good speaker.

regards and enjoy the music.
Raul.
Raul, from my earlier post, you know I agree with the benefits of subwoofer(s) to both extend low frequency response and reduce distortion on speakers and amps for the upper bass and midrange.

But I have a question for which I wonder if your experience may suggest an answer. At what frequency will these benefits diminish to the point where they may be of little value?

For example, I don't doubt adding subwoofer(s) while rolling off the bass on the main system will benefit a two-way speaker where the woofer is operating up to somewhere between 1,200 to 2,400 Hz before crossing over. Similarly it still benefits any three-way speaker where the woofer operates up to somewhere between 320 and 600 or so Hz. But what about a system where the woofer crossover is near the top of the accepted bass range, 160 Hz? If this is also a candidate for reduced distortion benefits to the upper bass and midrange, it would seem the subwoofer crossover would be quite low, say around 40 Hz. Is this correct?

Please share any experience that can answer these questions.
Dear Pryso: The range ( high/low )i the IMD depends mainly on the quality of the woofer driver and how low goes on the bass ( deep bass ).

Normally if the speaker croosover is set at 160hz to the mid-bass driver seems to me that that bass woofer could goes at least to the mid twenties.
The frequencies below 45-50Hz needs a biger woofer excursions that 50hz-up, these biger excursions are the main " culprit " ( not the only ) that the IMD goes high, so if you liberate this woofer from 50Hz down you will have improvement/benefits for lowering the IMD in the main speakers and a better main amplifier performance ( btw, we have to think that because a speaker does not have response, say, at 25Hz this does not means that the amplifier is not working in that frequency and below it. ) and obviously a better quality low bass performance through the dedicated subwoofers.
In this ( yours ) example the high-pass could be at 50-55HZ and the low-pass ( sub's ) at 80Hz, this depend if the filters are first, second or third order. So almost always we can have benefits through the sub's integration with passive main speakers.

As always the differences and improvements/benefits are system dependent and there are no precise " rules " on the subject other than " test and error ".

Regards and enjoy the music.
Raul.
Dear pryso: IMHO I think that there are some non know-how on the critical importance for the low bass reproduction.

Through the years I heard several full range speakers ( that goes down to 20Hz. ) including mines. In the last year I heard Wilson ( MAXX/Alexandria ), Acapella Triorlon, MBL 101, Dynaudio Temptation, Soundlab and Avalon " something " ( I can remember the model. ) etc, etc.
All very good speakers and if you never had/have the experience/opportunity to hear/heard a good powered subs you can/could think that any of those speakers is the only " thing " you need on the bass subject, all of them are good performers in the low bass but none has the quality level performance of a good powered sub.

You can say: so what? these speakers are great ones and we don't need anything else.

For me ( I can be wrong ) what define/makes the difference between ( talking about speker performance ) good speaker performance and very good/excellent one is its quality performance at both frequency extremes and for these frequency ranges the low bass maybe is the more critical because is the one that contribute the more to " pollute " the whole speaker performance. This is not something that someone tell me, this is my experiences about.

So IMHO till we have the right quality bass response by our each one speaker system we can't speak that we have a very good/excellent quality performance audio system.
Of course that every frequency range is important to the quality performance but I think that the low bass range is the one that can do more for the " bad ".

Regards and enjoy the music.
Raul.
Dear Pryso: The big Evolution Acoustic speakers are a good example of a full range design that does not needs external powered sub's because things are that the Evolution speaker design already have it and integrated to the speaker.

This Evolution speaker design is a good example where the designers take in count the critical importance of the low bass subject and the need that that bass range will be handled by a dedicated woofer/amplifier ( like the sub's. )

I can't say for sure the croosover frequency Evolution's woofers that handle the " sub " bass but maybe lower than 80Hz or maybe the owner can choose it.

Perhaps M. Levigne could share this info with us and can give us his thoughts/experiences on the sub's/low bass whole subject, could you Mike?, thank you in advance.

Regards and enjoy the music.
Raul.
For me as our living room is really big(11X12)I was hesitant in trying 2 subs.to some folks I might do things backwards.
in four years we bought a 900sq.ft. house,and of course I love audio.So I have been buying gear suited more for a bigger room.My speakers are revel 50as,Bryston 28B-sst+7B-sst+1X4Bsst,2XDD-15 subs.One which I have been using just for the .1 for movies.Raul suggested trying the 2 in stereo.
As I don't have much room I tried it in front of my speakers.One sub was good if you were sitting where I was sitting.Using two in stereo solidified the bottomend(Way more) and gave me way more soundstage depth,almost a 3-D effect.I imagine some are thinking,two DD-15s in a 11X12 room.And why i am I not using satellite for mains.the revels put out a nice bottom end(stereo direct)But adding a sub makes it way more solid,like a we'll recorded kick drum or bass guitar.adding two just makes it very enjoyable(more like a live event).I have no boominess,bloat,no nasties.I could only imagine when we add on to our house or buy a bigger house,how much more I'll get out of her.I thought two subs
might be too much(quite the opposite if you listen and be patient when adjusting the subs).I do Y cables out of my R+Lpre to amps and subs,speakers set to large.I have the subs X-over at 64 hz,as my speakers supposedly go down to 32-34 hz.I will try the X-over at 80hz and see.I like where their at now,very emotionally musically satisfied,BUT.Anyway it was a great surprize integrating the other sub,only one problem,I need another sub for my movies now,Thanks Raul.
Dear Drummermitchel: Nice to see that your sub's stereo integration was/is sucessful, congratulations.

Like you say we have to " listen and be patient " to achieve good results.
You even still have " land " to make a little change try it and listen for an improvement or not: to use the high-pass on your DD ones to liberate ( lowering the IMD on the main speakers ) your Revel's from low bass. You can do it and see what happen.

Regards and enjoy the music.
Raul.
Drummermitchel, did you mean to say "our living room is NOT really big(11X12)"?

Your post is a bit confusing. You reference buying a 900 sq. ft. home, then you say "So I have been buying gear suited more for a bigger room."

Now if you are happy with your sound, that is what really matters. It is just surprising to me that if your room is really 11' x 12' and you installed a pair of Revels and two DD-15 that you have room for the system to breath and image and you are not blown out by the bass. But maybe that was your point?
Dear Pryso: Yes, I agree with you: not really big.

This is the real " magic " of sub's alternative: it does not matters ( almost ) on the room because we are talking in the subs alternative mainly about low bass quality more than quantity.

In my experience two sub's always perform better than one in a room, two sub's makes the response be smoother.

Jloveys and Halcro point out that the ideal number is four sub's and there is the link to a scientific studies about made by Harman International elsewhere in this thread. Anyway the best way to go is when you listen it in your own system: you can't believe what you are hearing and the huge improvement in the quality system performance.

Btw, Dgob ( He posted in this thread ) has a very small room and he integrate two sub's in true stereo fashion with very good results too.

Regards and enjoy the music.
Raul.
It's kind of a joke as our living room is 11'X12",and yes that was my point.i tend to buy the best I can(to enjoy),and hopefully this year we'll add on or aquire a bigger house.
i know my system would love more breathing space,I can only imagine what she'd sound like in a bigger room.The room does give me some idea of what to expect,perhaps the calm before the storm.
Dear pryso: My " ask " to M.Levigne was because ( if I remember ) in their last three speakers in his audio system ( including the today ones ) he owned and own speakers that handle the low bass by self speaker powered woofers ( well I think that with his Kharma's he used the separate Kharma sub's ), so he already has a wide experience on the advantages to reduce the IMD on the speakers and the advantage to have dedicated drivers/amplifiers working in the low bass.

I hope he can read this and want to share his experiences about.

Regards and enjoy the music.
Raul.
Dear Pryso: I want to add ( a little late!. ) that even if the main speakers cross-over is at 160hz like you say and other benefits that the ones I posted earlier one advantage using separate self powered subs is that that separate subs can more easy be integrated on the room due that you can move it anywhere you need where in a full range speaker you can't because the woofer driver is an integrated part of the speaker and when you move the " whole " speaker to " tame " the bass response you " alter " too the full frequency speaker response .

In other side when you have separate self powered subs ( in true stereo fashion conection. ) using an external electronic crossover always your main amplifier will be liberate it for the low/deep bass response/handling and this means thet that main amplifier will perform better than full range, everything in benefit of an improvement in overall quality audio system performance.

Pryso from my experiences IMHO it is very very hard to beat a satelite/subs main system ( I support/recomended this kind of approach. ) against a non powered/passive non-separate full range speaker and even a self powered non-separate system.

Regards and enjoy the music,
Raul.
One of the things the speaker SYSTEM needs to do is cover the low frequencies to the same suitable extent as the other frequencies. That requires a suitable combo of amp and speakers. A "sub" in the sense of a separate device that covers the low range, may or may not be needed as well.

That pretty much covers it in a general sense I think. Beyond this, the devil is all in the details!
Dear Mapman: +++++ " One of the things the speaker SYSTEM needs to do is cover the low frequencies to the same suitable extent as the other frequencies. " +++++

certainly that is a " must " to have. Not an easy task but the effort to achieve it is worth on its rewards.
The subs integration has to be: seamless.

Regards and enjoy the music,
Raul.
Rauliruegas, I would agree except for supertweeters with no frequency response below 15k Hz. There I have found no integation issues. There are two of these that I know of-Muratas and Townshend.
Dear TbG: The ST integration in a system could be a " revelation " too because we are not waiting ( between other ST advantages ) that adding ST in our system the bass frequency range ( in especial. ) improves its quality performance just like the subs integration enhance the high frequency range.

I'm using the Tannoy ST with success. You can choose to cross at: 14khz-16khz and 18khz with a gain choosing between 88db to 95db.

I heard the Townshend but I prefer Tannoy's.

Regards and enjoy the music,
Raul.
Rauliruegas, I have no experience with the Tannoys. My only question is whether you hear music when only they are on. With both the Townshends and Muratas, you hear no music at all, just various pops and clicks.

What convinced me about the Muratas was a demonstration of them at CES years ago. They played music on a full range speaker with the Muratas on. Next they replayed the music with them off. All in the audience said almost as one, wow, put them back on. While the members of the audience were talking among themselves, there was silence. Finally, one guy asked what do the Muratas sound like by themselves? The demonstrator said you have been listening to them for quite some time. We all focused on what we were hearing and heard occasional pop or click. I bought a pair, and frequently did the demonstration for those visiting me.
Dear Tbg: In my system I really like ST. I bought the Tannoys because made a better match to my speakers but I like too the Muratas even that I never had the opportunity to heard it.

Using the ST gives to my system a quality performance improve at both frequency extremes.

Btw, the Tannoys " only " goes to 60khz not 100khz like the Muratas or Townshend, but works for me.

Certainly the ST integration in a speaker system is a lot easy than subs integration and because the rewards with both items IMHO are worth to try it.

I think that the " problem " with the subwoofers integration in a passive speaker system is the very low knowledge of the people and the same for STs.

Unfortunatelly ( like many other things. ) the AHEE already maintained the subs subject between " dense clouds " and that's why our poor understanding about and understanding of the subs huge advantages ( in favor of MUSIC. ) in a two music stereo system.

Regards and enjoy the music,
Raul.
Dear Tbg: Btw, AHEE means: Audio High End Establishment.

regards and enjoy the music,
Raul.
Here's my system:

Bryston amp 4B SST C-Series (2-channel)
Bryston preamp sp 1.7
Paradigm Reference Studio/40 v.2 (front speakers)
Paradigm Reference Studio Center Speaker CC / v2 (Center)
JBL PB12 12" inch Powered Subwoofer
Cambridge Azur 540D the CD/DVD Player

I listen to music 95% of time on 2-channel stereo and I don't like the bass on my music at all. The JBL sub did not blend well with my speakers. I am looking for more "tight" and "deep" bass for the music. What I noticed was that if I select the front speakers as "Large" and turn off the sub then the bass sounds better, but it is less bass and I wanted to be more.

The question is:
1. Should I upgrade my front speakers and get rid of the sub or should I replace sub for a better one?
2. What type of speakers sounds well with my Bryston amp? I like the B&W speakers, what do you think if I upgrade my speakers to B&W?

Thanks.
Vu,

Describe your listening room including size/approximate dimensions please.

Thanks.
Dear Vuluongchitam: IMHO your Studio 40 are good speakers and IMHO too it is on the subwoofer side where you have a " trouble ".

First, for listen music I don't recommend one subwoofer ( for very good reasons that you can read in this thread. ) but two units. Paradigm has very good options that can blend with your speakers better than the JBL but the word " blend " is the main subject here.

I take almost a year to stay where I'm today on the subwoofers overall subject inside my system, not an easy task where we not only need patience but good know-how about music and how music sounds " out there " ( live ).
Your speakers are " ideal " to be mated with subs: great combination if you take your time.

Please read what ( and other posts related. ) I posted in this thread that can put some " light " to you on the subject:

http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1117893153&openflup&27&4#27

http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1117893153&openflup&31&4#31

Regards and enjoy the music,
R.
Everyone would benefit with a powered sub....amps run cleaner just having to power the mids and highs, and the sub can be tailored for the room
I agree with Stringreen and Raul. You can get an all passive full-range loudspeaker system to give you all the bass extension and coherency you could want, but it's difficult, very expensive, and the speaker remains room-dependent. Pick instead a speaker with built-in active sub like the GoldenEar Triton 2 and you get a similar level of performance for much less money *and* have the ability to adjust the bass level to the room and the speakers' positions in the room.

I just added a very fast, small sub (Mirage MM8) to my Mirage OMD-15 floorstanders. The OMD-15s have decent bass, but it's much better with the sub. If I had the coin I'd probably have a pair of JL Fathom F112's, one sitting right next to each OMD-15.

This is also a killer way to get the most out of a pair of Magnepans. Add some fast lively subs to some 1.7s or 3.7s. I heard a pair of Maggie 20.1s set up with a pair of JL Fathom F212s a couple years ago. Awesome sound and very easy to listen to on a wide variety of music, and very competitive performance-wise with any $24K pair of conventional speakers. Or consider a pair of 3.7's plus a pair of Fathom F112's. Total price is $11K and a value leader at that price point.

The really good active subs with continuous crossover and phase controls can be seamlessly integrated into a system. You have to work at it a bit but it's worth it.
Everyone needs a powered subwoofer...if you have one, you need another...if you have 2 you still need another. Richard Vandersteen and I were discussing this very point. Woofers are the prime user of power from the amp. If done correctly, powered subs take the burden off of the main amp, and therefore the amp is loafing and working with an ease, that is clear to hear. Also, the sub can be placed more comfortably in the room to provide a smoother low end ...no hot and weak spots. Vandersteen says that he uses 4 subs and it really makes a difference
Dear Stringreen: Harman/JBL people made several studies about the " ideal " number of subwoofers for a smooth response and high bass quality, here is the link where one of their conclusions was that four subwoofers are the " number " but two subs are very good too:

http://www.harman.com/EN-US/OurCompany/Technologyleadership/Documents/White%20Papers/multsubs.pdf

and here what Vandersteen has to say about:

http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1117893153&openflup&84&4#84

Btw, Johnnyb53: maybe there is no " fast/slow " subs, please read this:

http://www.soundstage.com/maxdb/maxdb061999.htm

Regards and enjoy the music,
R.

11-12-11: Rauliruegas
Btw, Johnnyb53: maybe there is no " fast/slow " subs, please read this:

www.soundstage
Sounds to me like he *does* believe in faster bass, but somehow finds different words to express it. It's like saying that ice isn't slippery. Technically it's not, because the pressure of the object on top creates enough heat to melt a thin surface of water, which *is* slick. But it comes out the same place: step on ice, it's slippery.

By the same token, he can argue (speciously, I think) that the rise time at 40Hz isn't important, but a fast sub will have a fast rise time to mesh more easily with the rise times of the overtones of the bass note it's producing, and properly designed it should also stop quickly. This trait of speed makes it easier to blend the sub for musical purposes.

I agree that speed isn't all that important for car crashes and explosions in home theater (even there, better is better), but for music of most kinds it's absolutely essential.
Dear Johnnyb53: I think that the people can read the link and " form " their opinion about.

I agree with some of the points on that article. Sometimes is good to read 2-3 times articles like this one.

I tested along my audio distributors friends several times different subs as stand alone units and I can tell you that that fast/slow subs can't easy to detect.

The " perfect " integration in stereo fashion of subs to satelite speakers are a must and this can be achieved with fast/slow subs in the same system.
A stand alone sub sounds makes no music and even makes no sense when you heard. The relationship between the subs frequency response performance with/inside the satelite speakers is what it counts.

Anyway, the article opens a sligthly way of thinking on that subject.

regards and enjoy the music,
R.
Dear Stringreen: This is another Harman white papers on subs:

http://www.aes.org/tmpFiles/elib/20111112/13680.pdf

Regards and enjoy the music,
R.
Dear Johnnyb53: This are the experiences that an Agoner had in reference to that Soundstage subs article:

http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1117893153&openflup&340&4#340

Regards and enjoy the music,
R.