Acoustic treatment


I want to build my own bass traps and was wondering if there are any other alternatives to fiberglass and rokwool. Foam is not a consideration as I don't believe it has the necessary qualities for absorption. I have heard of cotton batting, does anyone have experience with this material. The idea of fiberglass makes me itch just thinking about it, but I'm resigned to using it or rokwool if that's all I have.  Please make suggestions and let me know your experiences.

Thanks
Mike
zardozmike
mijostyn:
"Boy are you out to lunch on this one Tim. It is not what you hear. It is about what you feel. I would bet that you have never played with a system in which you can control phase and arrival times which is why you have this rather flaky opinion. This makes a major difference in the realism of the system. Just wire one sub out of phase and see what you get. I've got news for you. You have to be in phase the entire cross over region. If you are 1/2 wavelength out of time you have one sub wired backwards. This would be the kind of biased unacceptable opinion you swarm guys would come up with. If you think the bass you have now is good, you have a long way to go. "

Hello mijostyn,

     Sorry I'm so late getting back to you, we went out for lunch and we waited about 3 months for our food! So, I literally have been out to lunch.
      I feel like you have a poor understanding in general about how and why the Swarm 4-sub distributed bass array (DBA) concept works so exceptionally well.  Here's a summary of some key DBA concept info to help you grasp it:

-Phase is important and the Swarm's phase can be continuously adjusted for the 4 subs as a group on the amp/control unit. Also, during the setup process one of the final steps is to reverse the phase on each sub individually to make sure the bass doesn't sound better with one of the sub's phase reversed.  
-The fact is that the very long bass soundwaves behave very differently than the much shorter midrange and treble soundwaves in typical domestic rooms.
-This makes sense since a full-cycle 20 Hz deep bass soundwave is about 56' long while a 20,000 Hz full-cycle high treble soundwave is a fraction of an inch long.
- It's been proven that we don't even hear a deep bass frequency under 80 Hz until the full duty cycle of the frequency sound wave has been released into the room, our ears have transmitted the details of the full-cycle deep bass soundwave to the brain and our brain processes this info as the perception of a deep bass tone present in the room. 
-In other words, we cannot detect the presence of bass under 80 Hz from less than one full wavelength. 
-We also need to hear multiple full wavelengths of bass under 80 Hz before we can detect pitch and volume.  A 56 foot 20 Hz sound wave released into a normal sized room means it is going to bounce or reflect at least once before the entire duty cycle is detected and be able to be heard at the listening position. We also need to detect multiple cycles at the listening position to determine pitch and volume.
-This implies that relatively small timing differences - 'small' relative to the wavelengths in the under 80 Hz bass region - are not going to make an audible difference in and of themselves. 
-The time domain aspect, or the timing of bass sound waves reaching the listening position, is of much less importance for deep bass frequencies than it is for mid-range and treble frequencies.  We're actually not very sensitive to arrival time in the bass region.
-There's no requirement for the correct timing so that the sound from each bass driver hits the listening position at exactly the same time like there is with the midrange and treble drivers.    
-The 4-sub DBA concept works so well due to creating numerous well dispersed additional bass room modes (bass peaks and dips) at various frequencies in the room. 
-The psychoacoustics identified principle of our brains processing these numerous varied bass room modes by averaging them out results in the perception of the bass as accurate, detailed, fast, smooth and natural.
-This is properly described as controlling the speakers to correct abnormalities of the speaker/room system, not as "room control".



Tim
 
noble100 "It's been proven that we don't even hear a deep bass frequency under 80 Hz"

Proven by who and where is this proof were you part of the study that proofed this I don't have a position on this either way but you have not provided proof while others involved in this conversation have provided to you specific references, quotes, and data and if I were you I would not discount, reject, or disqualify remarks made by Vandersteen he is one of the world's preeminent creators, designers, and manufacturers of speaker systems for Music Reproduction Systems.  
Hello clearthink,

       This is from an audio consultant named Bob Pariseau and he explains adding bass via subwoofers in the article linked below from his website.  He's in the 80-100 Hz camp.

   https://bobpariseau.com/blog/2018/6/5/choosing-a-crossover-frequency-awesome-bass-begins-here





noble100
"
 This is from an audio consultant named Bob"

Bob has no data, no studies, no scientific tests, no listening tests, no researrch, no references, hey he's just like you - you must be Bob you gave yourself away! Richard Vandersteen on the other hand has actual calculated, scientific demonstrated success in explaining, showing, and establishing that not all bass is mono now who do you think we should believe you, yourself, and Bob or someone who actually has done the study, work and science!
Hello clearthink,

     Okay, wiseguy.  There's lots of scientific White Papers on this subject from Dr. Earl Geddes, Dr. Floyd Toole and others.  These are easier to read, however.  I'd read them in order, Mehlau first and then the Dagogo interview with Geddes last.

https://mehlau.net/audio/multisub_geddes/


http://www.dagogo.com/View-Article.asp?hArticle=1047)


Later,
Tim