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Why the fascination with subwoofers?

I have noticed many posts with questions about adding subwoofers to an audio system. Why the fascination with subwoofers? I guess I understand why any audiophile would want to hear more tight bass in their audio system, but why add a subwoofer to an existing audio system when they don’t always perform well, are costly, and are difficult to integrate with the many varied speakers offered. Additionally, why wouldn’t any audiophile first choose a speaker with a well designed bass driver designed, engineered and BUILT INTO that same cabinet? If anyone’s speakers were not giving enough tight bass, why wouldn’t that person sell those speakers and buy a pair that does have tight bass?
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noble100's avatar
noble100
2,419 posts
 
rauliruegas:
"Not for you but for other gentlemans this link could help to understand better the overall bass management:

http://www.soundoctor.com/whitepapers/subs.htm "

Hello rauliruegas,

   First I read anything from the doctor.   I don't think the Sound Doctor is a good source of info for newbies.  He goes on about bass standing waves, bass room modes,  and bass sound wave timing as if he's not even aware of the scientific research and writings of Geddes, O'toole, Welti, Lejeune, etc. and that most of the in-room bass response issues he mentions can be solved through the use of a 4-sub distributed bass array system.  
     I'm not sure if he's aware of the dba concept and how well it works or not.  I wonder where the good Doctor got his degree from?  Do you think he just bought one on the internet?   
     It seems like he's the one in need of some bass management education.

Tim
audiokinesis
2,753 posts
 

@noble100 wrote: "But my main reason for posting is to ask about your quote above.
Was " and time-delay it such that it cancels the signal from the front wall when it arrives." accurate and not a typo?"

That’s what I meant to write.

My understanding is that the idea is to arrange four subs in a centered, half-the wall’s-scale pattern on the front wall. So if the front wall is 18 feet wide by 8 feet tall, then the subs would be at the corners of a rectangle 9 feet wide by 4 feet tall, centered on the middle of the wall. This mimics the best four-sub geometry Todd Welt found in his study of symmetrical sub arrays, but it’s on the wall instead of on the floor. If the wall reflections cooperate, they should cancel out standing waves in the vertical and side-to-side dimensions.

To cancel out standing waves in the front-to-back dimension, the idea is to use active cancellation based on an identical array on the rear wall. This array is in reverse polarity, with a time delay that corresponds to the length of the room.

So the subs in the front of the room to create a planar wave that moves to the back of the room and then disappears as the active cancellation array cancels it when it gets to the back wall. The "no bass" you mentioned happens at the rear wall, not out in the room, or so the theory goes.

I do not know how well this would work in practice. The answer is probably some variation on "it depends". Nor do I know whether it would sound better than a distributed multi-sub system. I haven’t really investigated it and will never build anything like it myself, but it MIGHT be a competitive "cost no object" approach.

Duke

bdp24's avatar
bdp24
10,008 posts
 
A number of years back, Danny Richie's GR Research system was voted as producing "Best Bass At The Show" by attendants of the RMAF show. Danny used a pair of Rythmik/GR Research OB/Dipole Subs at the front of the room, and a pair of Rythmik F12G Sealed Subs at the rear, their phase controls set 180 degrees opposed to the front subs.
noble100's avatar
noble100
2,419 posts
 
audiokinesis: "The "no bass" you mentioned happens at the rear wall, not out in the room, or so the theory goes."

Hey Duke,

     Okay, that makes a lot more sense to me now.  When I win the lottery, I'll buy a pair of Magnepan 20.7s and some extra bass panels, build a room and give you a call to try it out.

     I'll be living right on the beach somewhere. 
Thanks,
  Tim
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rauliruegas
13,112 posts
 
Dear @noble100  : The Sounddoctor is a point of view as can be yours, Audiokinesis or any one else and there is no reason that we can read it and the ones with more knowledge levels in the bass regards will took what is " rigth " and diminish what's wrong.

From some time now, I try to read the more I can on that regards.

When I started I did it alone with out knowing Harman or Geddes papers I just trust is what my nearfield live music experiences told me. Yes I took more time to achieve that " there " mentioned before that's what must be an audiophile target.

I have two true subs in a room with out bass traps and no equalization of any kind and I'm lucky enough to stay " there ". You are closer to that " there " so go for it, makes a difference and you will know when you experienced in your room/system.

Btw, I'm in this thread and in the other bass thread because I'm learning from almost every one.

I think that other than the Harman white papers no one  is owner of the " bass Bible ".
I know that reading " here and there " and following making some additional tests or making very little position changes or the like we can learn and perhaps a new kind of improvement. Well this is the way I think and the way I'm moving in my room/system, overall not only in the bass management.
My main target is to stay nearer to the recording.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
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