# Bass Trap, Tried it, What a difference!



## tonyvdb (Sep 5, 2007)

Well, after building my dream home theater room (although not perfect) I am thrilled with the results except on issue. I had a annoying upper low frequency peak around 80Hz that I did not like. It just got to be too much during some movies. I tried moving the sub to a different part of the room but I then lost allot of the db level that it had when it was in the front right corner of the room.
I had some leftover 8" wide acoustic "Quash" from work and placed them behind the sub in the corner at a 45 degree from floor to ceiling. ALl I can say is WOW what a difference that made! I had to turn up the sub just a little bit more but I am very happy with the results:clap:


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## Mike P. (Apr 6, 2007)

Glad to hear you found a solution, Tony. Could you explain what 8" wide acoustic Quash is? I tried a Google search with no luck. Thanks.


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## tonyvdb (Sep 5, 2007)

The "Quash" is made up of plastic like foam that is perforated, is flexible and about 4" thick (at least thats the thickness I have) and is specifically designed to absorb low frequencies.
Seen here
I highly recommend it to anyone who wants to build a bass trap.


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## Mike P. (Apr 6, 2007)

Thanks for the link. Any idea what the pricing is on it?


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## tonyvdb (Sep 5, 2007)

I'll look into it but it may take a day or so. You could try contacting Dow directly from that link above they have a "contact us" link on the side of the page.


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## bpape (Sep 14, 2006)

That's pretty amazing given the product specs. The absorbtion coefficient at 80Hz is off the chart on the bottom end being less than 0.1 I think maybe you got luck and are getting a membrane effect that happens to fit your needs. Whatever works though.

Also, I'm only seeing specs in the literature for 1", 1.5", and 2" materials. If you have anything for the 4", I'd love to see it.

Thanks,

Bryan


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## tonyvdb (Sep 5, 2007)

bpape said:


> I think maybe you got luck and are getting a membrane effect that happens to fit your needs. Whatever works though.
> 
> Also, I'm only seeing specs in the literature for 1", 1.5", and 2" materials. If you have anything for the 4", I'd love to see it.
> 
> ...


I'm thinking that I did get lucky, it may be the fact that I placed it at a 45 degree angle to the sub right in the corner. 
I measured the thickness of a peice that i have in the shop and its actually just over 3" but as you say the thickest they seem to show on the site is 2.4" Hmmm....
I will contact the company tomorrow that we had to install them to see where they get them.


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## Ilkka (Jun 8, 2006)

bpape said:


> That's pretty amazing given the product specs. The absorbtion coefficient at 80Hz is off the chart on the bottom end being less than 0.1 I think maybe you got luck and are getting a membrane effect that happens to fit your needs. Whatever works though.
> 
> Also, I'm only seeing specs in the literature for 1", 1.5", and 2" materials. If you have anything for the 4", I'd love to see it.
> 
> ...


I noticed the same. It seems to be pretty inefficient below ~300-400 Hz. They seem to be pretty much identical below 160 Hz, so I doubt the 4" is any better there.

OP: Are you sure it was the 80 Hz peak that got cured? Do you have any measurements?


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## tonyvdb (Sep 5, 2007)

Ilkka said:


> OP: Are you sure it was the 80 Hz peak that got cured? Do you have any measurements?


I just got home and removed the Quash from the corner I then ran some test tones through my system using a CD that I have that has tones from 5Hz all the way up to 25K and I was wrong it was higher at about 160-180Hz That still doesn't answer the question as to why its working so well but after placing the quash back into the corner as the 180hz to was playing the level of that frequency dropped noticeably (my mains may also be contributing to this problem but I have no control over the filter on my HTR as it was out before Yamaha started giving control over that I also dropped the same frequencies on my 3rd octave eq's that are on my mains but that had little to no noticeable effect. I dont know but its sure helping.


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## Guest (Oct 23, 2007)

I've just plonged into the world of acoustic treatments myself. I just received 12 2 X4 acoustic panels. Yes I know I could have built those myself but just no time!! I also ordered corner bass traps (the foam kind) and have noticed a noticable difference already. I had done measurements (REW) before installing the traps so I do have a basis for comparison but haven't redone the measurements yet. I'll keep you posted. But I can sure feel the difference, the bass is much more crisp (HSU stf-3 right behind the listening position)) As for the panels, I have yet to install them but my room has always been a bit bright. I should install this weekend. I'll let you know

Eric


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## Ethan Winer (Jul 21, 2006)

Tony,



tonyvdb said:


> it was higher at about 160-180Hz That still doesn't answer the question as to why its working so well


The most important bass problems are between around 80 Hz and 300 Hz. A lot of people think low bass is 30 and 40 Hz, but in truth higher bass frequencies have plenty of "weight" too. Now, imagine if you used something that really is effective down to 60 Hz and lower. :jump:

--Ethan


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## Doug Plumb (Mar 16, 2007)

Hi Ethan


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## Ethan Winer (Jul 21, 2006)

Doug Plumb said:


> Hi Ethan


Hi Doug.

:T


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## tonyvdb (Sep 5, 2007)

Talk about hijacking a thread :nono::bigsmile:

Anyhow back to the regularly scheduled program.... I found out that the quash is expensive, at about $200 for a 4x8' sheet its not cheep but as I got mine for free I'm not going to complain.:spend: and it worked really well in my situation.

Now to go and watch Spiderman 3:shh:


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## Scuba Diver (Sep 28, 2007)

Do you have any pictures you can post?


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