Do you think you need a subwoofer?

After adding a second sub to my system, there was smoother bass response. Again, this isn't about louder or stronger bass, in fact, I was seeking lower, smoother bass. Ironic that the path to this goal was accomplished by adding a sub! My girlfriend is a great listener and concurred that bass was better quality. Since I returned the second sub (on loan from my neighbor), I miss the performance. But, permanently adding a second sub may not be in my short term future. I already stretched to get one large horn sub in my room. A second is really bordering on impractical....

Dear Speedy: Now we can be in the same " channel ".

Regards and enjoy the music.
Raul.

Raul,as per your last thread,I finally DO get your point,which is valid.Best wishes!
Speedy!

Dear Sirspeedy: I understand what you mean and I agree with you.

+++++ " .We are still talking about low freq performance " +++++

Here it is our differences: you are talking about low freq performance and I'm talking about the whole frecuency range where the low freq is only a part of it. That's all.

+++++ " So I know exactly what you are talking about. " +++++

Maybe here is the problem: that you " think " what I'm talking about, but your posts tell me others things. Who knows?

Regards and enjoy the music.
Raul.

Raul,please don't preach to me.My thoughts certainly DO apply to this thread.I seldom see threads that stick,EXACTLY, to the exact subject.I,personally,like to see other "RELATED" viewpoints on subject material,that interests me.That is how one can come to a related piece of info,that could add a different perspective,to a topic.Which may be helpful.We are still talking about low freq performance,and if I can help to persuade someone that they do not have to fear complexity,or additional costs,of two subs,if they can implement one,than that's all my intentions are!!I fail to see your problem with this!

As for the 2 sub issue!!Raul,I have owned some of the BIG Infinities in the past!My friend's have these,as well as Pipe Dreams,with 4 subs.So I know exactly what you are talking about.That being said,I'll still stick with my previous comments,that one does NOT have to have two subs.It is room/main speaker related!Unless you simply must listen to movie soundtracks,all day at 110 db.Then Raul,you'll have to consider 4 units,like my friend has in his Pipe set-up.How about it?Ever hear 4 in your room?The little ceramic figures on your coffee table would not survive(that's a joke,btw)!

Dear Sirspeedy: +++++ " .If anyone wants to add "good" low frequencies,to an already good speaker,then the technology is readily available.The problem,to me,on this thread,is that some of the recommendations may scare away some potential music lovers,with the inference of needing 2 units,or additional crossovers.It is simply NOT true. " +++++

The problem is not on this thread. The problem is your approach about, you are talking of something really different for what this thread is all about.

The thread is extremely clear and is not a thread for to " add good low bass " like you say, this subject is for other different thread.

I urge you to read again an very carefully this link thread:

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

Here are the targets of this thread. Your concept is an old one ( I respect that ) an different from the whole subwoofers subject explain in this thread.

Please don't be or don't do that others people can be confused about.

Of course that the integration of two subwoofers in a true stereo way has its own trade-offs: need space room, two subwoofers, money, ettc., but what we can get for these trade offs in quality sound reproduction you can't imagine and every trade off about is justify. This is up to what any one want to have about music sound reproduction through their own audio system.
I can assure you and to any one: nothing come close to the integration of two subs in a TSW. Period.

Regards and enjoy the music.
Raul.

Dear Scott: +++++ " So why does almost everyone put the sub behind the satellites??? Aesthetics? Convenience? Sound? " +++++

I don't know for sure: sometimes for convenience, some times for sound or aesthetics.

When I start the integration of my subs I try at the corners ( behind the main speakers ) but does not work: bass too heavy. I try in line ( outside and inside ) with the mains: terrible. I try others room location till I finish with boths subs in front of the mains facing each other and in " open air " position.

If you take a look on speakers designs some of them have their woofers in a side of the cabinet facing each other: NHT, Coincident, Gallo, etc....

I know that everything about is room dependent but by coincidence like six months ago a friend of mine call me to invite to hear his new purchase: Velodyne DD-18. He owns ML with Levinson electronics.
He explain me all the DD-18 features ( very interesting ) and how easy to find te right position in any room and he explain me that the best position of the DD-18 was in the right corner behind the main speakers and front/firing.

Then we start to hear some music: classic, Jazz, rock, etc.., the sound was good but not good enough for what the system " have to offer ". Something was " wrong " with the bass ( only one subwoofer ).

I suggest him to put the DD-18 side-firing instead front-firing, we do that and Voila!!! the bass problem disappear. He do the measurements through the hardware/software in the DD-18 and he find that side-firing do an improvement in measurements too. Coincidence??

I don't have a sound degree to explain why the side-firing position could improve the bass response, but it works.

Regards and enjoy the music.
Raul.

Skushino - Audio Physics advises against subs in-line w/ mains. (see bottom of page)

"If you encounter any problems with this set-up, you may consider adding a subwoofer, which should not be placed in line with the speakers."

Skushino, I tried the subs in-line w/ mains....

I made sure they were both exactly the same distance from the front wall, then tried them outside and inside of the mains - near wall, away from wall.

Between the mains, things started to open up and deepen at about 4.5 ft from the back wall out to ~8 ft at the Cardas Golden Ratio for setup. The difference in depth of soundstage between those two distances didn't seem to be too great. But, I got a marked difference when I angled the subs almost 45 degrees towards each other (the middle). That added a lot of air and space.

Unfortunately, that was 2am and the differences could have been from fatigue. Like an idiot, the next day I started moving things around and cannot find that exact spot again.

But, when I moved the subs to the corners there was a noticable difference in depth. The only problem was that it seemd like the bass frequencies were slightly disconnected, lagging, or behind(time-wise) the rest of the music.(This was with the speakers 7 ft out and subs in corner) Nothing obvious, just a subtle feeling that kind of threw off the cohesiveness of everything.

As I moved the mains back toward the wall (and subs) the timing began to integrate again. Right now, at 4 ft. from the wall, the timing issue isn't readily noticable yet.

SirSpeedy's:

I'm going to try mocing the subs out of the corner more to see how that works. Oddly, I also have my mains 39" from th side wall. This places them at the null of 84Hz width mode(though sitting in the center-width of the room already deos this). So far, that seems to the best spot for maximizing soundstage width while maintaining imaging.

Darkmoebius,love your set-up,BTW.You seem to be following a very similar path as I did,when I tried integrating my sub "addition" to my main speakers.My friends ALL were against my adding a sub,in fear of poor integration.However with the technology available in low freq systems,I simply had to try to add that extra bit(I wasn't looking for much)of depth.Took me 2 years of auditioning too.

My room is a dedicated one 22.5x13x8,so I have my main speakers about 8 ft out,into the room.Floors are concrete.I have my sub behind the right speaker and a bit to it's right,in the right corner.Actually it is 22 inches from back wall,and 22 inches from sidewall.My main speakers are 39 inches from side walls,when measured to center of cabinet.Hope this helps.I sit 9.5 feet away from main speakers.This placement of sub,though always in right corner took EONS to get right!I'm talking about the "Rubics Cube" aspect of crossover point,placement,and gain setting.

You appear to be on the right track,and I'm sure you'll report back,soon,that you have found NIRVANA!!One thing:try to keep the main speakers out,well into the room,with really careful corner(NOT too close to corners though,as the subs need to breathe)placement of subs.I know you have to live in that room,but Audio is MORE important than your wife or mother in law's opinion!!Right?Besides a nice piece of shiny "BLING" always helps me,to get what I want.Try it!

What you are looking for(and I'm not trying to come off as an expert,so obviously feel free to improvise)is a superb sense of true "depth of soundstage",with a deep,but not overdone,sense of weight.Believe me,if you think the subs may be set too low,but are hearing low freqs and a subtle sense of pressure in room,on certain material,you are probably close to where you want to be.

Way too many set-ups are too bass heavy.When a mfgr or reviewer,for that matter,claims that the primary feature of a speaker system's impressive sound is the "GREAT BASS",that tells me it is,usually,too much bass!Which is fun,but destroys inner voicings,and subtle fine detail.Though plenty of people love this(ever pull up to a car with a MEGA BOOM BOX car system?Think he/she cares about inner voicings?).This can also,merely be my own taste.I don't care about cracking my plaster,but I do get off on a wonderful sense of inner detail,and soundstage depth,with a subtle underpinning of low frequencies;and to answer a suspicion by Raul--My crossover of 24 hz,does NOT impact anything above 40 hz.Careful set-up (not specs)has seen to that.Believe me,I would not want to go through it any time soon,but I am a fanatic.Guilty,but not sorry!!



Let's face it:when we are told a sub set-up will enhance the main speaker's midrange,it seems to me that the main speaker's mid is suspiciously lacking something.Usually the mid thickens up,when the low bass is too much,or even just a bit too much;but then there is a slight loss of subtle fine detail.It has to be sort of like Goldie Lox's porrage--JUST RIGHT!Then there is the magic,which I'm convinced you will have,as you have a "WORLD CLASS" set-up.Best wishes!!

Raul- On every single commercial sub set-up I have seen, the subwoofer is set up behind the satellite speakers, usually but not always in the corner. Every single white paper about LF acoustics describes a phase delay at these frequencuies.

So it seems that the subs should be placed at least even, preferably in front of the satellites, nearer the listener, if you want to compensate for phase. Only your system and one other guy I know has it set-up this way. the other guy's system is very nice.

So why does almost everyone put the sub behind the satellites??? Aesthetics? Convenience? Sound?

I am interested in your answer, but I will try placing the subs forward and draw my own conclusion.

Regards,
scott

Dear Scott and Darkmoebius: You are really trying hard the subs integration on your system. This is the only way to do it. We have to have: patience, very good " ears ", high musical experience, very good reference " sound " ( CD/LP ) and more patience.

+++++ " .When you get it "right",you'll immediately know it,as the system will "open up",while retaining proper "weight"!Best of luck! " +++++

Sirspeedy is right, but that is more easy to " tell " than to do it and that is the whole end of the subs integration.

One tip that works for me was: play a little with music with out bass or very little bass contents ( better with CD than with LP ) and compare with subs and with out subs. With this test you could know if the subs volume and crossover frecuency is on target or near target.

Other tip: for a little time don't do more " subs changes ", stay with what you think is " near to the best integration ": listen to your system for two-three days, then go to listen to a live event ( live music ), wait one-two days before you " play " music again on your system, after this " system break " start again with your system and do the adjustements that you think it needs.
If you can't go to listen to live music, then only do the " system break " for two-three times and " see " what happen.

Regards and enjoy the music.
Raul.

SirSpeedy, addictions are tough to kick...

You've got to ween yourself down a little at a time - cold turkey can kill ya'.

I've been slowly walking myself down the crossover point and volume range steadily. Surprisingly, the difference is increadibly subtle for such a large output difference.

But, as you suggest, lower levels allow more detail to sneak through. I also moved my subs to the corners(obvious, but I never tried it) behind my mains and moved the mains further out from the wall.

The corner loading actually reduced bass output from the between-the-mains position substantially. But, it also cleaned things up nicely. The lows aren't as obvious as before and blend well with the rest of the frequency range.

Corner ubs and mains farther from the wall created what my system has been lacking since I upgraded a few months ago - DEPTH!

Before, it was wide but flat. Now, I am beginning to get a sense of the distance between performers on stage with good recordings. And I get touches of that 3-D effect at times.

I tried the Cardas Golden setup, but that really wasn't any better than other positions and essentially rendered my living room useless with the speakers almost 7 feet from the front wall and my seating position 6 feet away. That's way too close for 6 foot tall speakers.

I hope to get a couple of other fanatics over to my house this weekend to help with positioning. It is just too hard to do alone with speakers this big. Get up, slide them a few inches, measure, re-measure, slide them again, sit down, listen some music, get up again and again and again.

After a while, it becomes impossible to tell the diference between positions. Yet, I slug on in the spirit of this crazy hobby.

Tonight my next door neighbor very generously agreed to loan me his sub for a couple of days, so that I can experiment with stereo subs. His sub has almost nothing in common with my horn-loaded sub, so the test isn't perfect, but it will do for my purpose. I have it located opposite my sub, in the right corner. I also want to evaluate both subs located even with and even slightly in front of the satellite speakers. This will be a little inconvenient due to the size and weight of the horn sub.

Will share my observations in a day or two.

cdc - By your reaction, I'm assuimg you had two high-end subs hooked up in true stereo mode with a high pass to your main speakers hooked up in your room? You found they didn't offer a suitable return on your investment?

Darkmoebius,you will find that as you lower the Sub output(using gain or placement,though you may try lowering cutoff point)there will be "Additional Information" that will appear,as well as a deeper soundstage.There will,also,be an even greater sense of high freq info.Too much bass will thicken up the sound,overall.Try listening without the subs.Then after a day or two,try to adjust for Maximum stage depth,with a very slight underpinning of low freq.When you get it "right",you'll immediately know it,as the system will "open up",while retaining proper "weight"!Best of luck!

"The first time you can hear the subwoofers right blended on your stereo home audio system: YOU NEVER COULD LIVE WITH OUT THEM AGAIN, ANY ONE CAN, period"

Nope. I can live very happily without subs and their associated costs and problems. Fortunately, spending lots of money is not required for me to enjoy music. Maybe when the industry can offer good products at fair, reasonable, honest, pricing (IMHO) I would consider upgrading.

"Too much Bass", an addiction! You are dead right, SirSpeedy.

I just started weening myself down off heavy bass out of my subs this weekend. For the last couple of weeks I've been listening to an artificially high level just because I could and it felt GOOD.

But, over the last several days I kept getting the feeling that it was too much. No matter how much I turned up my main speakers, the bass was just too prominent.

So, little by little, I've been turning them down. Not intentionally or conciously, just every once in a while I'd get up and turn it back a little.

It's still too much, but a lot less than I had. I figure by mid next month, I ought to somewhere near reality.

On a side note, yesterday I moved all the furniture out of my living room and moved my system to the other side of the room. Someone just tipped me off to the fact that I was losing a tremendous amount of midrange due to the open wall behind the speakers which looked down onto my dining room.

I also moved the subs in between my mains instead of outside them.

Good God, was he ever right! And my low frequencies are much more even now according to a test disc I've been using. I've only got two problem areas now - a massive 24-34Hz boost and a nearly complete suckout 54-64Hz.

This 24Hz bump is huge, but so little music strays into that I area I haven't noticed it as of yet, except for the test tone notes. Which is why I kind of like to think of it as a free sub amp EQ boost.

The 60Hz suckout is a different matter, altogether.

I don't think any of us have to act like any kind of salesperson,here.If anyone wants to add "good" low frequencies,to an already good speaker,then the technology is readily available.The problem,to me,on this thread,is that some of the recommendations may scare away some potential music lovers,with the inference of needing 2 units,or additional crossovers.It is simply NOT true.

Me?I really don't care if one does not want to explore the benefit of lowering bass frequencies.It is easy to be dissuaded(I hope I spelled that correctly).

Originally,when Avalon introduced their ported designs,in the Eidolon,it sent up a RED FLAG to me,because they had ALWAYS been insistent about the advantages of a sealed enclosure.They touted this "BIG TIME" in their owner's manuals.With extensive documentation,and scientific arguments in favor of the sealed cabinet.However,it was apparent that they could sell more product by making the enclosure more compact,and putting the HUGE external crossover (of my Ascents) in one cabinet.I had auditioned the newer ported designs at the time,but did not feel there was a big enough edge to move away from my current speaker.

About that time I discovered the REL line at HE 2001.I would have loved to add,just a bit of low freq depyh to my Ascents,and felt this would enhance performance if I could make a seamless transition.This,originally,like Doug's experience,was not the case in dealer systems.I kept coming back to the subject,for the next 2 years.Sterling Trayle(then of Sumiko)told me that my dealer was not demoing the Stentor correctly(the same dealer,Doug,who sold me the Triplaner).The dealer's manager,then,told me that I could have a money back guarantee,if the sub didn't work,as I wanted it,and Sumiko claimed it would.

Well it has been a fabulous investment(the manager was fired later,though it had nothing to do with his offer to me,but he was the ONLY good employee there).

Finally,and to me this is a HUGE point!Generally speaking,most hobbyists use too much bass.This is easy to do with a new sub,myself included.This is why I am so sceptical of any thoughts from either Raul,or anyone else,for that matter.Also,my advise should,also,be taken as just one more hobbyist,with a bass tuning set-up that is really an unknown commodity.

Almost always,I hear way too much bass from systems that have the capability to dole it out.Even my friends(except Sid,who is borderline,here)who have everything from Infinity's to Pipe Dreams,love to "DISH IT OUT"!!Fun,but not realistic!

The bottom line,and one reason a good one box sub set-up WILL work,is if you are careful,and don't get carried away,to simply underpin your low bass(extend it down,a bit,without overkill,which you WILL find hard,only because overkill is so damn much fun)you can EASILY be successful.It will take some time,but can be done,without a large investment or the extra space for 2 units(which is admittedly better,but not necessary,unless you are so fanatical,that you cannot live with one or two turntables.Or 5 cartridges aren't enough for you).Come and get me "R"!!

Anyone else wanting to "rationalize" not benefitting from low bass information,due to fear of costs,or system complexity,is losing an opportunity to add real insight to their listening pleasure.Make the effort to try it out.You may be pleasantly surprised!Best wishes!

Doug, a small cap can be installed at the input to your amp as a high-pass first order filter. This is how Raul is high-passing his main speakers.

In theory, the benefit is bypassing the sub high-pass filter with the more phase correct first-order cap, releiving the ampo of LF signals, while using the low-pass higher order filter in the sub only.

Hello Doug,

Adding the REL is a quick solution that most likely would result in a nice improvement without any chance of hurting your sound.

Ideally, you would want an external crossover so that each driver would get just what it needs but that is not an option for most of us. I personally would not want a sub with a full crossover to fed a speaker with a full crossover. One could still come out ahead but it would not ideal.

Anyhow, no end of things to try and people telling you to try them!
George

I think Doug would be surprised at the benefit from a single REL Stentor III crossed at 25Hz, but only by listening would he know for sure.

Thanks, George_a. Of course the REL methodology bypasses one of the advantages espoused by Raul, reducing the LF load on your main amp and speakers to allow them to produce the midbass and up with lower distortion. Which method is better? One could only know by trying both in the same system.

I've actually heard a Stentor, though not in my room or system. It wasn't dialed in properly so I didn't learn much. The system actually sounded cleaner without it.

Here's the official statement from REL on their "crossover" (called that for convenience since it is technically not a crossover as it does not have a highpass):

"The crossover is not a fixed low pass, but rather a more complex sloping rolloff. If you set the rolloff to 30 Hz, for example, it will play everything 30 Hz and below with no intentional rolloff. It will also play above 30 Hz, rolled off at 12dB per octave, until 80 Hz, where it will continue to play, but with an even steeper rolloff. This allows the REL to integrate as seamlessly as possible with your main speakers."

Thus with a 25dB crossover at 100Hz the signal is down at least 24dB, probably much more. However, the only way to know for sure what is going on is to measure which we are hopefully all doing.

I think Doug would be surprised at the benefit from a single REL Stentor III crossed at 25Hz, but only by listening would he know for sure.

Dear Sirspeedy: +++++ " then any low frequencies are perceived in "mono" anyway!.. " +++++

I don't know at which frecuency you are cutting your REL. But, for example, if the crossover is at 27-30Hz and if the low pass filter is of second to fourth order then your REL is reproducing frecuencies as high like 80-100Hz that does not percieved in " mono way " and that are interfering with the same frecuency range of your main speakers.

Any way, as I already told you what you or I " think " is irrelevant: only the " facts " count.

+++++ " ,you have NOT heard every room,or mine.. " +++++

You are right and I agree with you.

Regards and enjoy the music.
Raul.

Thanks SirSpeedy and Raul, for continuing to address the one sub/two sub question.

Of course I am in the ideal position to mediate, since I have NO sub! I can expostulate from a position of pure innocence, err, ignorance. ;-)

My decision is: you're probably both right. Assuming proper implementation, one sub is better than none, and two subs are much better still.

I don't for a second doubt Raul's statement that two subs make a huge improvement. He's done the work, he's heard the results.

SirSpeedy is probably correct that my speakers and his are similar in bass performance. Audiophiles who visit occasionally miss a bit of bass slam, but they are universally impressed with its articulation and tunefulness. As Raul said, there are quite a few excellent main speakers that will go down solidly and cleanly to 40 Hz or so. It's that last octave (and below) that's so difficult.

Hey,Raul!!I'm not arguing with you!My only real point was to sort of indicate to Doug,or anyone else interested,that if money is an issue,as well as space limitations,for two subs,you can get great results with one.That's it!

As for the stereo option,to my way of thinking,if one is crossing over as low as I am(and Doug's main speakers will most likely need),then any low frequencies are perceived in "mono" anyway!Now Raul---"THAT HAPPENS TO BE THE REAL FACT!!

The only advantage of the second sub(and one has to understand that there is a difference between how we configure a sub set-up.How low the crossover point,will have a huge impact on whether a stereo set will perform.EX:As I'm sure you know,a higher cutoff point will sound better with 2 subs.What you don't seem to grasp,Raul,is that if the main speakers are quality performers down to "nearly" the low octave,and you crossover "LOW",like 25-35 hz,since everything is already mono,at that point,the only advantage of the second sub is for evening out the acoustic energy(response),which may or may not be such a big problem,as the ROOM DETERMINES THIS!!

Now,before you kill me on this,which I know is coming,you have NOT heard every room,or mine,so give some consideration to this.Some hobbyists may be able to extend listening pleasure,and save a few bucks too!That is why Sumiko(Sterling Trayle,actually)argued I try one first.They were not out to ONLY sell product.Rare in this hobby.Best wishes!!

Dear Sirspeedy: +++++ " ).They felt that since my speakers had superb output down to 35-40 hz,and since my room was only 22.5x13x8,the "second sub" was not a "Real" necessity! " +++++

As you know your Ascents are not the only speakers that are " superb down to 35-40 Hz ". I can tell you that the moment when you can integrate two subs in a true stereo way in your system: you will be shocked!!. The Sumiko people loose/missed the real subs subject.
Btw, what you think or what I think about is totally irrelevant, what is relevant is a FACT and that fact will tell you anything about: the FACT : " the integration of two subs in your system ", you have to try it, you have to heard it at your place: is the only true way to really knows about.

Regards and enjoy the music.
Raul.

Don't worry Skushino,

I have to wait until my girlfriend goes to bed before I can watch SciFi Channel or play computer games. And I'm 40 years old! Talk about a dork.

I tried a listening session tonight of one sub versus two(summed mono). Same songs, same passages, seconds apart. Out of that rudimentary test, it seems to me that one sub gets you 80% or more of tonal benefits. But, the second sub adds depth and texture to what's there.

As for energy or room mode cancellation, I kinda got the feeling that I have less problems with one sub than two. How's that for weird? One of my subs must be slightly out of position because it is supposed to cancel a lot energy.

I played a few deep bass laden tracks (Bach organ, Bjork, Pink Floyd) and then walked up to the master bedroom which is on the floor above and behind the living room (tri-level house). There seemed to be more energy in that room with two subs than one. Although, one was still enough to annoy someone in bed.

I think absorption/basstraps are the only real answer to your(and my) problem. Since I have two subs pointing directly forward, I really don't need the added room gain. So, I am going to experiment with DIY absorptive panels on the wall behind the speakers and bass traps in the corners. The same behind the listening position to drain energy away from the wall 2-3 behind my head. I'm also going to put panels at the 1st reflection points.

As a single-sub user for all of a couple of months, I am considering a second sub. My reasons have to do with smooth and even bass performance, NOT more bass. My single sub is in the front left corner. There is plenty of bass energy, and I have the level turned to almost inaudible. What I have a problem with is the uneven response. Some LF energize the room much more than others.

On a side note, my girlfriend complained about the bass keeping her awake while I was listening late at night. The music level was pretty low, in consideration of her. My home is three levels, listening room on the bottom floor, bedroom on the third floor. When I went upstairs to investigate, the music was barely audible. But when I put my ear to the pillow or bed, the bass was rumbling through. My conclusion is that airborne energy dissipates quickly as a function of distance (inverse exponential function) while the structure is a more efficient conduit for LF energy. I believe my single sub generates plenty of energy, but needs some attention to refinement. Perhaps anti-vibration footers designed for industiral machinery would hep. Anyone try this? Interestingly, I have no problems with vibrations affecting TT playback on my suspended wood floor. But the TT is a Micro Seiki...

My flame suit is on, ready for the jokes about listening to music while my lovely girlfriend is in bed. Gosh, I must be such a geek....

Regards,
scott

Doug,I know you are a knowledgeable guy(you too Paul),but I'd like to add some thoughts,as we have some common denominators re main speaker bass output and sub integration.

I have a speaker that extends,extremely cleanly to about 40 hz in room.Maybe a bit lower.My intent(since I previously owned Infinity RS-1b's and IRS-Betas,both stereo sub set-ups,BTW)was to integrate a deeper bass response,without affecting the overall presentation of my current speakers,which I LOVE,and will not consider moving away from!

I only wanted to add frequencies below 35 hz.I actually have my sub crossing over at 24 hz,a gentle roll off above that freq allows a perfect blend with my Avalons.

For practical reasons(as well as financial overkill)I opted for a REL Stentor series II.Placed in the right corner,just behind the main speaker.A little playing around yielded fine results.This has really turned out to be a wonderful configuration,in my room.I was not looking for audiophile bass.I wanted a "subtle" underpinning of low frequencies,while retaining the stunning timbres of my "sealed box" Avalons.I feel that although my big boy Infinities were more power oriented designs,my current set-up obliterates them in seamless perspective,openness,stage presentation and amazing timbres,while implementing a very natural deep bass integration,but NOT bass overkill,which many hobbyists are addicted to.I still can't believe what a dumb move Avalon made by discontinuing such a fine design( easy load,sealed enclosure with stunning mid bass and dynamics,external crossover,massive build,beyond newer models,more weight etc).Well I guess WAF of smaller designs is better for bottom line,but my money is on the Ascents I own.As a matter of fact,I have been told by two industry "higher ups",independently,these were the best speakers Avalon ever made.I don't know,but really don't care.My point being,to pull just a bit more from them,without breaking the bank.Something I'd already done,with all my stuff,anyway.

Now I know Raul loves the idea of a stereo integration,and I'm sure a second sub will benefit me,but it just ain't happening.The performance,currently is SO strong that to my way of thinking,the second unit is not worth it (financially),if you don't have a very large room,and are getting a high level of performance,with one.

Before Raul begins to "rail" at me(I still love you,Raul),let me say that I called Sumiko,before adding the sub.I was ready to go for two(stereo).They felt that since my speakers had superb output down to 35-40 hz,and since my room was only 22.5x13x8,the "second sub" was not a "Real" necessity!

As of now,I'm thrilled,as I think you can be be,since I know you are very capable.I also think your B&W's are similar in output,and presentation to my speakers.Best of luck!!

Dear Doug: Tks God Emily pass through our country ( twice ) with not many damage like everyone waiting for. Tks for ask.

regards and enjoy the music.
Raul.

Darkmoebius,

Thanks for the insights. Like you, if I can get another .03% for just $10-20K, I'm all for it! ;-)

Our rings-like-a-bell Salamander Synergy is (somewhat) isolated from the trampoline floor. Each of its eight feet is sitting on a heavy duty sorbothane hemisphere. The rack and all the equipment on it push the sorbothane to its designed load limits, so its benefits are pretty much maxed out. This does help, but a quieter rack on a solid floor would help alot more. I'm afraid those will have to wait until my next lotto ticket comes in.

Raul,

Thank you for the honest answer, which I sort of expected. :-( With all the timing and phase integration issues, it only makes sense to have a sub for each main speaker, as close as possible. Otherwise you're risking sonic mud. Your description of all the work you did to place your subs was very eloquent.

I'm sure the one-sub, bass-is-not-directional idea was invented to sell subs for HT explosions, while keeping the decorator happy by not putting two more large boxes in the middle of the room.

If one sub isn't worth having, we'll just have to wait until the room grows a bit. :-(

It's funny. The cubic volume of air "seen" by our speakers is pretty large, 26 feet x 18 feet x 7.5 feet. Apart from the low ceiling that's probably more space than many speakers get. But the room layout is restrictive. There simply is no space near the speakers for subs, and no other way to arrange the room.

Some day...

BTW, is Hurricane Emily missing you? I hope no one close to you is affected.

Regards,
Doug

Doug

Dear Doug: There are many critical subjects/issues for to have a better quality sound reproduction at home. The integration of two subwoofers in a true stereo way is one of the most critical subjects and where any body can hear the great improvement that we can achieve.
Almost ( before this thread ) no one on this forum talk in " deep " about this sub subject.

We all always are talking and looking for a better quality sound reproduction through our systems: TT, cartridges, tonearms, phono preamp, VTF,VTA, etc... , I think that the sub subject is more important and is time to care about and enjoy all their advantages.

No, I don't think that will be worth to add one sub to your system: you need " room ".

Regards and enjoy the music.
Raul.

You're right, Doug....

I don't own an equipment rack or isolation system yet, so I actually have to place my turntable down below in the dining room and use long IC's to get it away from LF energy right now. When notes hit those room mode frequencies, the panel in my fire place starts to buzz and the windows vibrate.

So, it's not really worth it(using TT) for me until I get a good rack and room treatments. Getting up to run downstairs every 20 minutes or less is beyond silly.

But, having said all that, the difference a sub (or subs) make in the texture of bass and midrange is astounding. My main speakers are similar to yours in FR(~40-36kHz). Though, in reality, I'd bet you've got a lot more 40-60Hz output than mine.

Anyway, everything is much more fleshed out. There's just so much more "body" to instruments and vocals it is surprising. Not in a "slam" or "punch" style, but the actual resonance of the instrument. Tonality and texture have jumped into the next league.

I can't speak to spatial information yet because of my room problems, so others will have to jump in for that. But, suffice it to say, I cannot stand to listen to my mains anymore without the subs. They sound weak and anemic in comparison.

Pretty surprising considering two weeks ago I thought they did a terrifc job of producing deep, tight, bass for horns. I still do, though nothing close to what I've got now.

But, since you've already said in your system description that the Salamander Synergy Triple 20 is "Too resonant for a serious audiophile, but looks nice in the LR", it's a safe bet that you'd have to get a new equipment stand or a lot of isolation platforms, blocks, rollers, pads, etc. Then, there's the inevitable room issues to keep you occupied for a good long while, especially with only on spot for sub placement.

Aaaw, screw it - go for broke! That's what this silly hobby is all about - spending money and chasing that last 5% of performance. You'll never know what your system is truly capable of until then(just joking).

Raul,

Thank you for starting and supporting a truely informative and interesting disucssion. I just read the entire thread (not counting all the helpful links, yet). This is a great resource for those looking to further improve musical reproduction in the home.

We don't have a sub (or subs) yet, and space constraints may prevent us from adding any, unless we buy a bigger house or add a music room to the existing one. Putting two subs in front of our speakers (or anywhere) would be impossible. There would be no space left to walk through the living room.

The most we could do at present would be to add a single sub, and it would have to go in one particular corner, behind and outside the right speaker. There's a foot or two to play with but that's about all.

Do you think that would be worth the expense and trouble? Another factor to consider is our very lively suspended wood floor, which already sends too much energy into the equipment rack. Lightening the load on the amp and main speakers makes excellent sense, but shaking the electronics and turntable with alot of LF energy doesn't. Help!

Thanks,
Doug

Dear Todd: I think that the man with the Dynaudio speakers have or a room's problem or a Velodyne High-pass filter problem in his sub.

A high-pass filter is a very simple design subject, there is no " high technology " here or " genius " know-how.

If, like the people of Velodyne say, the high-pass filter of the DD series is the same than in the HGS series: don't worried about, is a good one. Btw, don't worried about that specific phase issue on that thread.

Stay calm.

Regards and enjoy the music.
Raul.

Dear Raul and others,

I ran into a thread on avtalk.co.uk specifically about using the high-pass filter in the Velodyne DD series:
http://www.avtalk.co.uk/forum/index.php?t=msg&th=11392&start=0&rid=0&SQ=0

In this thread, it is observed that the phase of the signal that is passed beyond the high pass filter is quite variable. There is a chart here where someone with a DD18 created to demonstrate this. The poster then goes on to recommend not using the high-pass filter on the Velodyne DD series. Raul and others - do you feel as though these phase variations are a major problem? Minor problem?

Thanks for sharing thoughts

Todd

Dear Darkmoebius: It looks great. I will try this week-end ( if I can ).

Regards and enjoy the music.
Raul.

Hi Raul,

I just burned RealTraps Test Tone CD onto a blank cd and have been playing with it for an hour or so.

It's amazing how much output jumps on in the frequencies where there are room modes. Fells like 5x the volume or more.

Dear Darkmoebius: You can try the CD from the original soundtrack film: Sneakers. REL suggest to use it in the four track for test the subs room integration.

Regards and enjoy the music.
Raul.

Good idea Sstark,

I'm going to get a decent SPL meter this week to help check my room problems with some test tone cd's, anyway.

It's reassuring to hear that you are actually corssing in the subs that high(as compared to standard 80Hz) because my intial tests over the last week or so, seem to indicate that the 100-120Hz range works best in my room. It's hard to ell where in that range it falls because Paradigm doesn't provide precise numbering along the dial, nor would that matter because I understand that the pot can be up to 20% off.

Anyway, I've been using two or three cello works for tuning the crossover frequency - Kronos Quarter "Gnarly Buttons" & "Pieces Of Africa", and Roger Kellaway's "Cello Quartet". There are also some excellent blues/jazz bartone works that I've noticed get "fleshed out" with the higher setting.

80Hz seems to be a "cleaner" setting, but 100+Hz tends to help out cello, piano, organ, etc.

BTW, Terry Cain suggests using push-pull tube amps with the passive subs. And he said they don't have to be monster amps to get great sound, so I'm considering some vintage PP organ amps. I figure they had to be able to push some current in order handle sustained organ notes in cathedrals/churches.

Experiment. The bass may appear fragmented or incomplete but it works its auditory illusory magic with considerable authority. Put on a piece that has critcal bass, e.g. Yo Yo Ma Bach Sonatas. Ensure the bass and upper frequencies are balanced. Then measure the sound levels three ways: combined, bass only and without bass. You'll be surprised how high the dbs are for bass only. I use a separate modded BK 442 (200wpc) amp to drive a pair of separate passive sealed 10inch Hales bass drivers through an active crossover so its always adjustable. I turn the bass way down on poor bass recordings where the woofer just pumps, e.g. sadly RCA LP Heifetz/Reiner Tchaikovsky Violin Concerto; I couldn't do that with an internal three way fixed crossover. A modded BK M200 monoblock (200wpc) amps drive the mid/tweeters. I'm always surprised how much presence the bass driver creates and how hard the bass amp works. Through countless trials I now set the crossover at 120hz. A cello works the bass amp harder than the mid/tweeter amp. I can feel the difference in the heat sinks.

Thanks for clearing that up Raul, I was just a little worried that I somehow burned up my subwoofer crossover. Everything sounded great when both the subs and main speakers were playing, but when I turned down the mains, the subs sounded muted and out of focus.

Amazing what an influence such a bad sound can have. I thought instruments and voices sounded pretty damn good before, but now after hearing things with the subs, mains-only sounds thin and one dimensional.

The subs added depth and flesh to everything. Amazing because it does so with very little output. It really doesn't take very much volume wise. Although, what little it does, pushes my 275 wpc sub amp to it's limits on organ music and other sustained low frequencies.

Dear Darkmoebius: What you are hearing is right: "Everything was rather muted in a undefined way. ".

For the low bass reproduction has " means " for our " ears " it has to be working with the midrange sound, other way ( 80Hz and down ) you will heard what you already heard.

Regards and enjoy the music.
Raul.

.
Great thread guys; thanks for sharing the great information.
.
Rgds,
Larry
.

What does it sound like when running strictly a subwoofer or two below 80Hz?

And what should I listen for when adjusting phase?

I finally got a decent amp for my pair of passive subs, a Samson Servo 550 (275wpc). It's a pro/live amp used in clubs/bars/etc.

Anyway, I feed my subs via a Paradigm X-30 active subwoofer crossover with line-level inputs.

I am currently feeding the X-30 directly from my cd player's "fixed" outputs and my monoblock tube amps from it's "variable" outs while rebuilding my passive transformer volume control.

Anyway, last night while playing assorted jazz, classical, and rock I would intermittently turn the volume down on my main speakers to listen strictly to the subs output.

I expected to hear distinct, clear-cut, drum strikes or the clean resonance of standup bass strings, but that isn't what I got. Everything was rather muted in a undefined way. It certainly fleshed things out when mixed in with the mains speakers, but I expected more attack, I guess.

The best description would be a line that an audio reviewer once used - the subs recreate the trailing edge of a note rather than the leading edge. More resonsce and decay than strike.

I've tried varying the x-o frequency from ~60Hz-120Hz.

Does this seem right?

Dear Todd: Congratulations for your choose !!. The high-pass filter is the one that do the crossover for the frecuency range that will handle for the main speakers, example: frecuencies from 80Hz and up; and the low-pass is the filter that send the frecuency range to the sub, example: 80Hz and down.

The parametric EQ allow to perform adjustements with a specific frecuencies, that's it that the filters in a parametric EQ are variable and with a variable Q ( broad band ). In a graphic EQ the frecuencies and the Q are fixed.

Maybe you will have to use both of these EQ. You can know it when you try to do the integration to your system/room.

Regards and enjoy the music.
Raul.

I think this is one of the most important threads on Audiogon for all to read and understand.

I have purchased a Velodyne DD15 (should arrive in about 4 weeks), and when funds allow I will try adding another for true stereo low freq. I'll experiment with crossing over my Dynaudio S1.4s ~80hz and see how that goes.

Questions: What is the difference between high-pass and low-pass? Also - on the DD series, there seems to be a graphic EQ as well as a parametric EQ. The parametric EQ has a Q value that can be modified. Is that parametric EQ something that I would want to fiddle with, or should I be able to accomplish everything with the more simple visual EQ? The velodyne documentation is a little light on describing what the purpose of the parametric EQ is relative to the visual EQ.

Thanks,

Todd

Screenshoot of my RoomModeCalc ouput.

Unfortunately, in the length mode, the closest my speakers can be to the rear wall is the 2nd order 47Hz null(5.75ft). Which makes sitting at te preferred mid-room 1st & 3rd null (12 ft) serious near field listening six feet from the speakers. That just doesn't work for me.

But, it is possible to sit right in between the 3rd & 4th nulls at 19.75 ft and 20.75 ft. Both the 71Hz and 95Hz modes should be as close to their nulls as possible.

On the other hand, the 24Hz mode will be at it's absolute worst. Since I don't have an amp for my subwoofers yet, and the main IM-Ben's only go to 40Hz, this shouldn't be a problem. When I do have an amp, EQ'ing that mode down should be no problem.

I kind of like that solution because I didn't want to add any crossover into my main fullrange signal outside of it's stock 12dB/octave high pass filter for the super tweeter.

Skushino - Fantastic article!!!!!

I didn't get the concepts the first time I read it, but the next morning I went through it again using the Excel Room Mode Calculator spreadsheet with my room measurements and everything made sense.

First of all, I had to re-measure my room because I realized that I was using a false length distance AND I got my room width wrong. I had been using 16'x20'x8', when in reality my room is 15'x23'10"x8'. Length-wise, I hadn't accounted for the distance that the rear wall that extends back over the dining room.

Then, using the Room Mode Spreadsheet, I was able to find the proper 12' mid-length seating position at the 1st & 3rd(71Hz/24Hz) order nulls. Then, position the speakers at the 2nd order 5.75'(47Hz) null. That leaves me with the lone 4th order 94Hz length mode.

Width-wise, sitting dead center of the room puts me at the nulls of the 1st & 3rd (38/113Hz) modes. I can then put the mains and subs exactly on the the 2nd & 4th nulls (75/151Hz) at 2ft & 3.75ft from the side walls. That looks to provide almost complete cancellation of the the width problems.

So, by experimenting with speaker & seating placement< i should be able to do away with most of problem bands except the single 94Hz legth mode. Although, I an sure I can find a way to dampen that one, too.

Unfortunately, I won't get a chance to try any of this out until next Monday because my brother and his wife are visiting with their 2 year old. Everything gets packed away from Natasha's curious fingers.