[DougSmith]

No - that was just at my LP.  Here is the averaged response of three listening positions (the three spots on my couch)...
I wanted to try the natural rising thing but never got around to it.  Oddly enough, my receiver does it on its own, so my response looks more like yours for movies, but its flatter (as shown above) for music.  I think it turned out well for both, and I only had to apply three filters of EQ.  I am pretty happy, all things considered.  Your response looks amazing, by the way.

That looks great...  Your room seems to be better behaved than mine. I use a DCX2496 to adjust the subs. It provides a lot of flexibility and works very well for this application.  I am using 9 PEQ notch filters per channel (most of them are very narrow and not very deep), basically wherever there is a modal peak.  Modal ringing is well controlled as well (the large couch is a good bass absorber). Smoothing hides a multitude of minor issues, but my unsmoothed average looks about the same from 20-100Hz.  I might add a third sub someday, just for fun.

[jqp]

Here is another chart that shows down to 25Hz



Here is a wavelength chart, hard to believe the wavelength at 200Hz is 5ft!




 

[Nuance]

That looks great...  Your room seems to be better behaved than mine. I use a DCX2496 to adjust the subs. It provides a lot of flexibility and works very well for this application.  I am using 9 PEQ notch filters per channel (most of them are very narrow and not very deep), basically wherever there is a modal peak.  Modal ringing is well controlled as well (the large couch is a good bass absorber). Smoothing hides a multitude of minor issues, but my unsmoothed average looks about the same from 20-100Hz.  I might add a third sub someday, just for fun.

Very nice.  I am using the 1124P, as I never thought I'd need (or want) more than one "uber sub."  I was wrong and have benefited from two subwoofers.  A third is inevitable and should be the icing on the cake.  I'll wait until I buy a home before going that route, though, as I hope to be moving the system into a dedicated room at that point. 

jqp,

Great find!  To add to yur wavelength chart, here is the wavelength calculator:
http://www.mcsquared.com/wavelength.htm

The general rule of thumb concerning subwoofers is that each one should be placed within 1/4 the wavelength of the crossover in distance (feet), else phase and delay issues can occur (so if using an 80Hz crossover, which is a wavelength of 14.125', the subs should be placed no farther apart than 3.53' in order to prevent said issues) .  This is why devices like the DCX2496 have individual phase and delay settings.  Of course, Toole, Dr. Geddes and others in this thread have stated delay/phase doesn't matter in the nether regions, so perhaps my statement is moot.  I'll have to experiment more in my friends system (warpdrv - quad 18" DIY sealed LMS subwoofers). 

[Quiet Earth]

If your sub was level-matched, why would you alter the settings based on the recording?  It should still remain matched.

That's a good question that I don't know how to answer. Why indeed.

[Nuance]

That's a good question that I don't know how to answer. Why indeed.

+1 (or is is +2?).  Although, I do know people who adjust the subwoofer output on the fly depending on how much they are in the mood for.  To each their own, so long as it makes you happy. 

[Quiet Earth]

I was one of those people.    I could never decide if it sounded right or wrong, so it made me unhappy..... 

[mort]

I prefer to keep my sub at 0db of gain for 90% of listening material I do however find a few recordings that require slight ajustments. If I am listening some rap or  audio from a movie I have to reduce the gain considerably.

[jqp]

I prefer to keep my sub at 0db of gain for 90% of listening material I do however find a few recordings that require slight ajustments. If I am listening some rap or  audio from a movie I have to reduce the gain considerably.

Yeah this is a real aggravation with bass - you are reducing gain, where 99% of the folks out there are hearing less bass and it is also distorted!

My speakers do 33Hz at -3dB, I can't imagine what is happening in millions of homes with HDTVs...much less CD players.

[rollo]

That's a good question that I don't know how to answer. Why indeed.

  Quite simple actually. Not all bass is at the same level of the rest of the music. "Sound Wars" for all recordings. Especially pop and rock recordings from my experience. Phase as well if you can dicern it.
  A remote that can control volume and phase separate from the main system is a blessing. Until I heard a demo of such never knew it made a difference. A big one.

charles


charles

[woodsyi]

Cowboy Junkies' Whites Off Earth has vastly different  bass mix between the original and the Mofi remaster.  Most of the time, I have to turn bass down on their original mix.

[laserman]

The title of this tread through me off.  As one poster stated, it would be blasphemy not to use subwoofers in certain applications.

Early in my audio enthusiasm journey I became a fan of dipole electrostatic speakers.  My first introduction was via KLH 9’s, which rolled off starting at 70 Hz.  I progressed to Quad, Martin Logan, Sound lab, Acoustat, and even magnet driven Magnepans.  As many of you are aware, the disadvantages of these types of speakers include a lack of bass response.  This is due to phase cancellation from a lack of enclosure, and the difficult physical challenge of reproducing low frequencies with a vibrating taut film with little excursion amplitude.  While bass is lacking quantitatively, it could be of better quality ('tighter' and without 'booming') than that of conventional cone designed systems. 

Phase cancellation can be somewhat compensated for by electronic equalization  [shelving circuit] that boosts the region inside the audio band where the generated sound pressure drops because of phase cancellation.  Nevertheless maximum bass levels could not be augmented because they were ultimately limited by the membrane's maximum permissible excursion before it got too close to the high-voltage stators, which would most lightly damage the speakers.  Several of these companies started to experiment with stepping up the bass (30-80 Hz) in their XO designs or build hybrid designs incorporating subwoofers.  All of these faced mixed reviews on integration of these applications.  The quest then and today is to find designers who can produce fast, tight and detailed subwoofers.   

As a prior owner of a couple of those manufactures listed above, I was always on the hunt for a fast, tight and accurate sub that would not bring attention to itself.  I owned a few of them back in the day and own three today.  To my detriment and out of pocket expense, room acoustics didn’t enter into the equation until much later than it should have.  Knowing what I know today, I can look in my rear view mirror and realize I sold items which probably would have stayed around longer had I tweaked my room.  Oooh well, lessons learned - sometimes you get the bear and sometimes the bear gets you.   

Throughout the most recent twist and turns of my audio journey, I have heard speakers where a sub wouldn’t have added any value to the sonic signature and others anemic without one or two.  It all has to do with the design of the speaker, room acoustics and personal preference.

In summary, I still don’t understand where the blasphemy comes from since subs have been in my life for five decades.  My personal preference - subs crossed over low, low output and PEQ'd metered out to remove any humps.  OBTW, IMHO HT folks (I don’t mean to be disrespectful, so no flames please) muddy up the sonic air waves because most like the house curve hump in the bass.  This can be gleaned by how they write their reviews of subs….my pants legs were flapping, my windows were shaking, I bet my neighbors could hear these beast….

[Nuance]

What subwoofers are you using, laserman?

[RUR]

  Quite simple actually. Not all bass is at the same level of the rest of the music. "Sound Wars" for all recordings. Especially pop and rock recordings from my experience.

An ongoing effect described by Toole's audio "Circle of Confusion".  See Sean Olive's blog on this here: http://seanolive.blogspot.com/2009/10/audios-circle-of-confusion.html

A random sampling of ones own music library will quickly confirm the variation in sound quality that exists among different music recordings. Apart from audible differences in dynamic range, spatial imagery, and noise and distortion, the spectral balance of recordings can vary dramatically in terms of their brightness and particularly, the quality and quantity of bass. The magnitude of these differences suggests that something other than variations in artistic judgment and good taste is at the root cause of this problem.

[cujobob]

  Quite simple actually. Not all bass is at the same level of the rest of the music. "Sound Wars" for all recordings. Especially pop and rock recordings from my experience. Phase as well if you can dicern it.
  A remote that can control volume and phase separate from the main system is a blessing. Until I heard a demo of such never knew it made a difference. A big one.

charles


charles

That's obvious, but it wouldn't change if it were main speakers or the sub.  With a sub, being able to adjust bass is a good thing in that situation.  With mains alone, you can't and you're stuck with the bass on the recording...good or bad.

[laserman]

In order of personal preference:

Rythmik 12” - sealed
Adire Shiva 3 12” – sealed
Vandersteen 2W modified with Apex Sr. amp tricked out - sealed

[rajesh]

I'm reviving an old thread. Are there any change of views / divergent opinions / addendums?

[Elizabeth]

When i owned B&W 805S speakers i had added a small sub.
Problem with it was the sub was perfect for acoustical music, or Jazz, or chamber music, but had to be turned down or off for most Rock and Roll.
Now i have Magnepan 3.6s and no need for a subwoofer.
I can proudly make the sacrilege statement that the overexaggeration of the low freqencies started with home theater, and was reinforced by car stereo. Now with all the reisues of Rock with the bass artificially exaggerated (plus endless compression)l makes most Rock really unlistenable with any sort of sub in a two channel system. Unless of course one just wants a gut massage, and to feel there eyeballs vibrate. (It has to be really loud for that effect, trust me.)
This comment from one who despises any form of loud one note boom-boom-boom trash. And expects the low frequencies to be a part of the actual music, rather than some special show of it's own.

(and I hate faked car crashes, where the cars ALWAYS explode, When did you ever see a real car crash and an explosion? never, they do not exist, except in movies. Same for super bass.
HAH.

[HAL]

The GR-Research Super-V's have built in open baffle servo subs and sound great!   I use them for all styles of music and work well for them all.  I had Maggy IIB's with dual VMPS subs at one point and B&W 805 Matrix Series II's with Genesis 12M Servo subs and sounded very good after setup. 

I still prefer stereo subs over a single.   

[rajesh]

When i owned B&W 805S speakers i had added a small sub.
Problem with it was the sub was perfect for acoustical music, or Jazz, or chamber music, but had to be turned down or off for most Rock and Roll.

That may be because of your room most probably. Rock music being inherently having a lot of bass content, will overwhelm you if the room aids in amplifying the LFE.

[toddbagwell]

I run my mains full range, and add in the subs from 40hz and down to fill in where the speakers/room start to roll off.

The result is solid and smooth without any boominess.

It does help to identify what is happening with a set of measurements. You can easily see what frequency is causing the boom, and move speakers or add treatments to reduce it.


Happy listening

Todd