The importance of a good subwoofer [Archive] - Audio & Video Forums

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emaidel
03-08-2008, 05:17 AM
I'm sure it comes to no surprise to anyone who has read some of my past postings here, that I'm an avid fan of the Dahlquist DQ-10. Few speakers have maintained their reputation as have these babies, and they are still often compared to others costing far more, and do very well in those comparisons.

Still, there's no denying that the DQ-10 is desperately in need of a subwoofer: its bass performance just about stops at 50HZ, and not too much is readily audible even above that.

When I first bought my DQ-10's, I did so without a sub. I was working for Pickering at the time, and Saul Marantz had enthusiastically endorsed the Pickering XSV-3000 cartridge as the best sounding MM cartridge he'd ever heard. I offered a "salesman's accommodation" price to Dahlquist employees on the XSV-3000 of only $20 (half of dealer cost), and most snapped up the offer. Then, one day, a Dahlquist salesperson told me that I had no idea of how good the bass performance was on the XSV-3000 (which I was using at the time) if I didn't have a subwoofer.

So, I purchased the DQ-1W sub and the passive crossover. Wow! I was amazed. A few years later, I purchased the electronic crossover and used a separate amplifier (a bridged apt/holman) to power up the DQ-1W, and it sounded even better.

So, to make a long story endless, after inadvertently destroying the DQ-1W, I purchased a self-powered Definitive Technology SP-15F sub which significantly outperformed the DQ-1W. I don't believe it's manufactured any longer, but other quality subs are.

I had noticed when listening to my system recently, that the sound seemed to be a bit thin. EMI recordings sounded downright shrill, and with little or no bottom information, especially when compared to a Telarc recording (Telarc always has a ball recording bass drums, and often at a woofer-damaging level too!). So, I made two very slight, but very dramatic adjustments: I raised the crossover point on the sub (it's not clearly marked as to just what frequency, but it's continuously variable from 150 to 50HZ, so I guess it's now around 100HZ), and slightly increased the level as well.

The difference was nothing less than astounding. I don't have an overabundance of bass, nor is the sound "tubby" or anything like that. There is a newly-added "fullness" to many instruments, particularly bass fiddles and trombones, and even male chorus members. And when those Telarc/bass drum smacks occur, they do so with a vengeance! And, just to be sure the level wasn't too high, or the crossover point too high as well, I played the Saint Saens "Organ" symphony (#3) and listened carefully. The low pedal notes all but shook the foundation of my house, but there was no "boominess" to the sound, so I think I lucked out at the settings.

So, what's the point of all this rambling? In Definitive Technology's lit with the sub, they make it very clear that there's no "right" setting for the crossover points, nor the level, and that the user should experiment with those settings. I always exercised caution, and kept the level settings on both fairly low, but now realize that was a big mistake. Coupling the DQ-10's clear, detailed sound (and their fabulous imaging) with thunderous bass is really something, and I suspect, such a statement is valid for many other quality speakers too.

So, unless anyone owns a speaker system which in and of itself is capable of reproducing extremely low frequencies (and, I dare say, most speakers - even very good ones - aren't), if that person doesn't own a good subwoofer, then he just has no idea what he's missing. The results are very, very satisfying indeed!

basite
03-08-2008, 05:52 AM
tried a sub with my thiels...

hated it...

the sub was just too 'slow', and the x-over setting didn't go low enough. It always sounded wrong, phase was wrong, timing was wrong, and not only the bass suffered from it...

maybe it needed more time to set up (and a better sub...), but I didn't like the results when I tried it.

and I can't complain on the bass, those thiels pack some serious punch and go really low already...

Keep them spinning,
Bert.

emaidel
03-08-2008, 06:07 AM
tried a sub with my thiels...

hated it...



and I can't complain on the bass, those thiels pack some serious punch and go really low already...

,
.


I suspect your Thiels are one of the few speakers that go low enough not to need a sub. Perhaps if they needed one, Thiel themseles would make one, and they don't. Of course, your match was clearly not a good one, and your observations are understandable.

audio amateur
03-08-2008, 06:08 AM
Which sub did you use Bert?
I have to say I'm quite happy with my 686's bass, i can only imagine a sub destroying the sound, but then I've only ever played with cheap subs.

basite
03-08-2008, 07:20 AM
Which sub did you use Bert?
I have to say I'm quite happy with my 686's bass, i can only imagine a sub destroying the sound, but then I've only ever played with cheap subs.


A B&W ASW 600, I imagine a REL quake or higher could make a better match though :p


Emaidel, Thiel does make subs (darn expensive ones...), which flawlessly integrate with thiels (they have an external crossover specially made to integrated with thiels). I'd say that unless you start listening to big (really big) pipe organ music, which has subsonic frequencies in it, you don't really need a sub with the 'bigger' thiels (you could use one with the CS 1.6 though)

there are still lots of speakers today that can reach the very low frequencies, it's just different then back in the 60's and 70's that you'd need a 15" woofer to do that...

Keep them spinning,
Bert.

blackraven
03-08-2008, 10:17 PM
A REL sub or one that is at least servo controlled should fit with your Thiels Basite. The higher end RELs are known for their speed. They match very well with Maggies. So do the Martin Logan subs.

Florian
03-10-2008, 12:16 AM
The problem aint speed, its resolution ;-) 20Hz will always be 20Hz, there is no slow or fast. The problem is the resolution, room, phase etc... Try some new Velodynes with the room correction software, use two in stereo :-)

Sir Terrence the Terrible
03-10-2008, 12:43 PM
I suspect your Thiels are one of the few speakers that go low enough not to need a sub. Perhaps if they needed one, Thiel themseles would make one, and they don't. Of course, your match was clearly not a good one, and your observations are understandable.

My main left/right speakers are -3 at 20hz, and can play 25hz at 118db with less than 10% distortion. In order to get even more headroom, and take a little stress off the mains(they have never overloaded even at extremely high SPL) I still bought two big servo controlled subs into my system to handle the LFE channel.

Subs with room correction will not help with integration. Its the crossover AND the arrival time of the sub that does that. Some subs are just plain difficult to integrate because the crossover is not steep enough, not flexible enough, or there is a audible delay of the arrival time of the mains and subwoofer. Using crossovers designed for my speaker and subs, and having the correct arrival time dialed into my sub, I had no integration problems with my full range mains, and my subwoofers.

E-Stat
03-10-2008, 02:07 PM
I'm sure it comes to no surprise to anyone who has read some of my past postings here, that I'm an avid fan of the Dahlquist DQ-10. Few speakers have maintained their reputation as have these babies, and they are still often compared to others costing far more, and do very well in those comparisons.
I have always enjoyed their sound since I sold them back in the 70s. Wasn't crazy over the piezo, but they were easy to disconnect.


So, what's the point of all this rambling? In Definitive Technology's lit with the sub, they make it very clear that there's no "right" setting for the crossover points, nor the level, and that the user should experiment with those settings. I always exercised caution, and kept the level settings on both fairly low, but now realize that was a big mistake.
I'll add to your recommendation: getting the upper bass / lower midrange right is critical for the natural reproduction of many instruments. I have a pair of powered subs (really bass modules since they run out of steam around 35 hz) in the HT system mated with some small monitors. I experimented greatly with the high pass to the mains, low pass on the subs, and finally used EQ to ensure the smoothest overall response (there were two peaks and valleys between 60 hz and 160 hz) This I verified with a Rat Shack SPL (using adjustment curves) and calibrated third octave test tones. While my approach is not as accurate as using a high quality RTA arrangement, it nevertheless ended up with a very natural sounding result.



So, unless anyone owns a speaker system which in and of itself is capable of reproducing extremely low frequencies...
I am quite fortunate in that the in-room response of the full range electrostats in the main system is virtually flat to 25 hz (completely disappears below that though) which is quite sufficient for my tastes. Albeit at far less than ear shattering levels (peaks in the low 90s) possible with Sir TtT's big horns or Flo's giant Apogees!

rw

Sir Terrence the Terrible
03-10-2008, 02:51 PM
I have always enjoyed their sound since I sold them back in the 70s. Wasn't crazy over the piezo, but they were easy to disconnect.


I'll add to your recommendation: getting the upper bass / lower midrange right is critical for the natural reproduction of many instruments. I have a pair of powered subs (really bass modules since they run out of steam around 35 hz) in the HT system mated with some small monitors. I experimented greatly with the high pass to the mains, low pass on the subs, and finally used EQ to ensure the smoothest overall response (there were two peaks and valleys between 60 hz and 160 hz) This I verified with a Rat Shack SPL (using adjustment curves) and calibrated third octave test tones. While my approach is not as accurate as using a high quality RTA arrangement, it nevertheless ended up with a very natural sounding result.{/quote]




I am quite fortunate in that the in-room response of the full range electrostats in the main system is virtually flat to 25 hz (completely disappears below that though) which is quite sufficient for my tastes. Albeit at far less than ear shattering levels (peaks in the low 90s) possible with Sir TtT's big horns or Flo's giant Apogees!

rw

E, did you say something?? Something about my shattered ears.....

filecat13
03-11-2008, 06:14 AM
The problem aint speed, its resolution ;-) 20Hz will always be 20Hz, there is no slow or fast. The problem is the resolution, room, phase etc... Try some new Velodynes with the room correction software, use two in stereo :-)

While two incorrectly placed and calibrated subs can be awful, two (or four) subs properly deployed will add fantastic resolution, clarity, and quickness. They won't always be phased alike to have maximum effect. By "effect" I'm not referring to boominess or loud thumping; I'm writing about smooth, quick, effortless LF reproduction in a specific room.

I guess I'm an advocate of the "many hands make light work" school of thought when it comes to deep bass. Of course, it helps to have reasonably big hands, though not necessarily monstrous ones, unless the room is large enough to require them.

blackraven
03-11-2008, 10:01 AM
I think that many people don't really know how to properly adjust the settings on a sub. A subs volume or output should be turned down till you can barely hear it and then just a bit more. Most people have their subs turned up to high. You should not hear a sub but you should get the feeling of fuller bass and lower frequency,and added warmth. Now I'm only talking about stereo music here, not HT.

Sub placement in the room is another issue as is the cross over settings. You have to try different positions in the room to get the best sound.

I know must of us on this forum know all this but I'm sure there are a few who don't.

E-Stat
03-11-2008, 10:12 AM
I think that many people don't really know how to properly adjust the settings on a sub.
And, depending upon your system, it is possible that you could never get it right. A next door neighbor where I used to live had small in wall speakers and a huge 18" sub. No matter how he adjusted the sub, there was always a hole in the mid bass.

Naturally, he cranked the sub to shake the walls. :)

rw

blackraven
03-11-2008, 08:28 PM
Basically a sub should disappear and into your music so that you don't know that its there.

And in talking about the speed of a sub or how fast the bass is, we are really talking about its Dampening, which has to do with how well the enclosure is made and baffeld as well as if its ported or not and servo controlled. Non ported subs tend to be "faster" or dampen unwanted woofer movement better than non-ported subs. There are many factors that make a sub "fast". Sub's that dampen better are much better for faster paced music and speakers.

pixelthis
03-12-2008, 12:27 AM
Basically a sub should disappear and into your music so that you don't know that its there.

And in talking about the speed of a sub or how fast the bass is, we are really talking about its Dampening, which has to do with how well the enclosure is made and baffeld as well as if its ported or not and servo controlled. Non ported subs tend to be "faster" or dampen unwanted woofer movement better than non-ported subs. There are many factors that make a sub "fast". Sub's that dampen better are much better for faster paced music and speakers.

SUBS ARE AN IDEA WHOSE TIME HAS COME.
And gone.
The plate amp burning out on my asw 1000 is the best thing that happened to me.
I am a new devotee to stereo bass.
I NOW have a pair of Axioms (m80s) with plenty of bass and have said goodby to subs forever.
I am getting some of the best imaging and solid image I HAVE HAD IN YEARS.
I guess subs will always have a place in HT, but for music two big honkin floorstanders
ARE IT:1:

E-Stat
03-12-2008, 07:13 AM
And in talking about the speed of a sub or how fast the bass is, we are really talking about its Dampening, which has to do with how well the enclosure is made and baffeld as well as if its ported or not and servo controlled.
While those are important factors, ultimately, *speed* is determined by bandwidth.

rw

GMichael
03-12-2008, 07:19 AM
While those are important factors, ultimately, *speed* is determined by bandwidth.

rw

Cables & crossovers?

blackraven
03-12-2008, 02:47 PM
Subs still play a role in 2ch music. Certainly small book shelf speakers benefit from a sub. Especially with people who like HT and 2ch stereo but do not want larger speakers or have space limitations. A sub allows you to have small speakers because you can easily hide a sub under or behind furniture or in the corner of a room.

The problem I see all the time with subs is that people end up buying a very cheap sub or too large a sub and dont know how to adjust it.

E-Stat
03-12-2008, 05:06 PM
Cables & crossovers?
Bandwidth of the woofer / bass system, all factors included.

As a passionate follower of proper bass timbre (getting the harmonics right), I prefer woofers with wide bandwidth. Like the Sound LAB full range stats that go beyond 20khz. That's my woofer.

rw

MacKee
08-13-2009, 04:22 AM
E, did you say something?? Something about my shattered ears.....


I know this thread is old, but I must ask Sir Terrence a question...

How did you configure the m-508 to run the sub? Did you bridge it?

Auricauricle
08-13-2009, 05:20 AM
I originally bought a sub under the premis that doing so would smooth out and improve the palpability of midrange material. I also wanted to accentuate bottom end material on various compositions that is often more sensed than heard, such as the low thrums of bass-viol pizzicatos, etc. At this time, the latter goal has been met somewhat. Meanwhile, I continue to experiment with equalization to adjust timbral characteristics, tweaking a bit here to get more wood outta the woodwinds and more tin from the brass....

JoeE SP9
08-13-2009, 07:48 AM
I can not tell a lie. I originally got a sub because I wanted "honkin'" bass. Being able to hear the 32Hz Organ note in Thus Spake Zarathustra was and is cool. Now with 2 serious subs and the woofer box that came with my Spectra's I've got all the bass I ever wanted. The woofer cabinet is only in use with surround material because it's connected to my surround speakers. With 2 channel material two asymmetrically placed subs are what the doctor ordered. I'm a happy camper.

Jimmy C
08-13-2009, 07:50 AM
... it was called the "Smart Sub"... something like that.

They don't make them anymore?

Auricauricle
08-13-2009, 10:23 AM
Oh: honesty time. HAD to hear the 16 Hz on Tocatta and Fugue. No luck yet, but gettin' there's been mighty fun! So, two subs, eh? My wife'll KILL my asparagus!

Luvin Da Blues
08-13-2009, 11:26 AM
With 2 channel material two asymmetrically placed subs are what the doctor ordered. I'm a happy camper.

Couldn't agree more. I run two Infinity 10" subs, crossed over around 55Hz, and I don't think I could get a better bass responce with just one. I run these subs in stereo.

It has been mentioned in previous threads that anything below 80Hz is omnidirectional. I'm from the school that says each channel would have a different bass responce, depending on the mixing and panning of each instrument. I would perfer to deal with any phase cancellation acoustically rather than electrically (ie; internal or external mixing [Y connector] of the lower frequencies).

Sir Terrence the Terrible
08-20-2009, 02:55 PM
tried a sub with my thiels...

hated it...

the sub was just too 'slow', and the x-over setting didn't go low enough. It always sounded wrong, phase was wrong, timing was wrong, and not only the bass suffered from it...

maybe it needed more time to set up (and a better sub...), but I didn't like the results when I tried it.

and I can't complain on the bass, those thiels pack some serious punch and go really low already...

Keep them spinning,
Bert.

Bert,
For your information, there is no such thing as a "slow" woofer or subwoofer. There is such things as phase issues which are often mistaken as slow woofers, and such a things as subwoofer hangover in which the sub driver resonants after the signal stops. There is also such things as standing waves and room resonances which are room and placement related and have really nothing to do with the subwoofer itself.