Andy Sneap & Backstage Productions  

Go Back   Ultimate Metal Forum > Heavy Metal Forums > Andy Sneap > Backline
Register FAQ Donate Members List Calendar Mark Forums Read

Backline Gear, software, plugins, samples, IRs ...

Reply
 
LinkBack Thread Tools
Old March 16th, 2011, 02:43 PM   #1 (permalink)
::XeS::
Senior Member
 
::XeS::'s Avatar
 
Join Date: Mar 2005
Location: Italy
Posts: 4,547
Bass trap....what's the truth?

Ok, yesterday I wrote a thread on Gearslutz about bass traps.
In my home depot I found only 2 kind of absorber:
- some kind of Isover panels, 2" thick, 145kg/m3 density
- big rolls of fiberglass, very soft, 1" thick, 40kg/m3 density

I asked wich one is better to build basstraps and broadband absorbers and they said me the less dense.
Said that they started explain me that a 2"-4" basstraps don't do anything below 100Hz. If I want some kind of absorbtion below 100Hz I need 20"+ basstraps O_O
Is it true or they are maniacs as usual?
I've never seen 20"+ basstraps (only if they are some corner traps).
Do you advice to use the less dense for basstraps and broadband absorbers?
::XeS:: is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:22 PM   #2 (permalink)
roflsaurusrex
"Brootz"
 
roflsaurusrex's Avatar
 
Join Date: Jun 2009
Location: New Jersey
Posts: 1,865
obviously 20 bass traps is a bit crazy for a smaller studio. 8 would be a solid number in my mind. 1 to each side of you, 1 in each corner, 1 above you, 1 or two behind your monitors. I don't have too much experience so take that like a grain of salt.

I don't go on gear slutz because they always answer everything with an infinite budget
roflsaurusrex is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:27 PM   #3 (permalink)
jipchen
Max
 
jipchen's Avatar
 
Join Date: Nov 2008
Location: Munich, Germany
Posts: 2,528
I'd go with superchunk basstraps for the corners.. they are obviously very effective in the low end.
And that's no gearslutz saying but the result of measurements (I agree the people on gearslutz are often exaggerating)..

2" is indeed very thin, most broadband absorbers I've seen are at least 10cm (about 4 inch) deep.
Imho the most competent people are on http://www.johnlsayers.com/phpBB2/index.php
There are huge threads about how to build them, how deep should they be, what's effective and what's blabla, etc.

edit:
Just an example of broadbandabsorbers:
http://www.mbakustik.de/dateien/BAB_...tionswerte.pdf
THE BAB50 is 5cm, BAB100 is 10cm and the BAB150 is 15cm deep. At 125 Hz a 5 cm absorber has an asborption factor of only 0,20..

Last edited by jipchen : March 16th, 2011 at 03:36 PM.
jipchen is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:32 PM   #4 (permalink)
::XeS::
Senior Member
 
::XeS::'s Avatar
 
Join Date: Mar 2005
Location: Italy
Posts: 4,547
Quote:
Originally Posted by roflsaurusrex View Post
obviously 20 bass traps is a bit crazy for a smaller studio. 8 would be a solid number in my mind. 1 to each side of you, 1 in each corner, 1 above you, 1 or two behind your monitors. I don't have too much experience so take that like a grain of salt.

I don't go on gear slutz because they always answer everything with an infinite budget
I was speaking about the depth (inches/cm) not about the number of the traps.
20"+ means something depth 50cm or more..
::XeS:: is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:34 PM   #5 (permalink)
jipchen
Max
 
jipchen's Avatar
 
Join Date: Nov 2008
Location: Munich, Germany
Posts: 2,528
Also, if you place them with a space between the wall and the actual absorber, it significantly increases its effectiveness.
(edit Actually, the common opinion on some forums is: if you cover the low end with effective bass traps (i.e. superchunks), the other acoustic panels are good with 2" plus 2" space from the wall.

Last edited by jipchen : March 16th, 2011 at 03:37 PM.
jipchen is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:35 PM   #6 (permalink)
PhilTheBeard
"The Beard"
 
PhilTheBeard's Avatar
 
Join Date: Jun 2009
Location: Cape Coral, Florida
Posts: 2,678
20 inch deep bass trap seem's a little retarded to me. I think 4 inch trap's would do you a world of good.
PhilTheBeard is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:44 PM   #7 (permalink)
::XeS::
Senior Member
 
::XeS::'s Avatar
 
Join Date: Mar 2005
Location: Italy
Posts: 4,547
+1, that deep can only be reached with corner traps
::XeS:: is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:46 PM   #8 (permalink)
Jarkko Mattheiszen
The FU guy.
 
Jarkko Mattheiszen's Avatar
 
Join Date: Jul 2006
Location: Lappeenranta, Finland
Posts: 6,461
Quote:
Originally Posted by demisephil View Post
20 inch deep bass trap seem's a little retarded to me. I think 4 inch trap's would do you a world of good.
It's anything but retarded. Four inches of any material will only do you so much good. Otherwise any small cubicle could have perfectly tuned low-end just by slapping four inches of absorbing material on all surfaces. Obviously, that's not the case.

Seriously, read up on the John L. Sayers forum. There's some golden acoustics information there, both theoretical and practical.
__________________

WWW - FACEBOOK
Recording - Mixing - Mastering
Jarkko Mattheiszen is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:55 PM   #9 (permalink)
jipchen
Max
 
jipchen's Avatar
 
Join Date: Nov 2008
Location: Munich, Germany
Posts: 2,528
FWIW, my corner traps are between 50 and 100 cm deep (they're angled obviously) and the effect was HUGE by just building one of them. I'm super stoked for the remaining three. The improvement was instantly recognizable (also by other people), and I had lots of absorbers before that, the difference was never that big.
jipchen is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 03:55 PM   #10 (permalink)
PhilTheBeard
"The Beard"
 
PhilTheBeard's Avatar
 
Join Date: Jun 2009
Location: Cape Coral, Florida
Posts: 2,678
Quote:
Originally Posted by Jarkko Mattheiszen View Post
It's anything but retarded. Four inches of any material will only do you so much good. Otherwise any small cubicle could have perfectly tuned low-end just by slapping four inches of absorbing material on all surfaces. Obviously, that's not the case.

Seriously, read up on the John L. Sayers forum. There's some golden acoustics information there, both theoretical and practical.
Hmm..... I'll def read up on this guy's stuff. But i know in the room i work in all we have is 4 inch trap's everywhere and it make's a huge difference in our room.
PhilTheBeard is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 04:09 PM   #11 (permalink)
Jarkko Mattheiszen
The FU guy.
 
Jarkko Mattheiszen's Avatar
 
Join Date: Jul 2006
Location: Lappeenranta, Finland
Posts: 6,461
Quote:
Originally Posted by demisephil View Post
Hmm..... I'll def read up on this guy's stuff. But i know in the room i work in all we have is 4 inch trap's everywhere and it make's a huge difference in our room.
Oh, I didn't mean 4" panels won't help, they definitely do, but only to an extent. I've got a combination of suprechunks, 4" bass traps and broadbands and 2" broad/highbands, and I could still use more
__________________

WWW - FACEBOOK
Recording - Mixing - Mastering
Jarkko Mattheiszen is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 04:41 PM   #12 (permalink)
::XeS::
Senior Member
 
::XeS::'s Avatar
 
Join Date: Mar 2005
Location: Italy
Posts: 4,547
What about the density?
::XeS:: is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 05:08 PM   #13 (permalink)
jipchen
Max
 
jipchen's Avatar
 
Join Date: Nov 2008
Location: Munich, Germany
Posts: 2,528
Quote:
Originally Posted by ::XeS:: View Post
What about the density?
I never dug that deep, so I personally can't help you there

But this should clear things up a bit:
Quote:
Originally Posted by Mikas Mietshaus Akustik View Post
absoprtion is not related to the destiny of a material, it is related to it`s flow resistivity.

It is important to have a optimal flow resistivity related to the absorber depth.
When you use some insulation with high length specific flow resistivity and make the absorber to deep, the soundwaves will be reflected, and don`t flow through the whole deepth of the absorber. When the absorber is thin, and you use insulation with a to low length specific flow resistivity, there is not enough resistivity to transform the sound energy into heat.

Remember, we talk about porous absorbers only.

The location of the absorber is as important as it`s porperties.

The destiny of rockwool, for example is nearly twice the destiniy of glasswool, with the same length specific flow resistivity.
The reason is it`s different porosity.


cheers
Mika
Project Studio Build
It's a quote taken from my studio construction thread.
jipchen is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 05:26 PM   #14 (permalink)
crillemannen
Senior Member
 
Join Date: Jun 2007
Posts: 3,200
My bass traps that are in front of me is about 50cm deep. And the one at the backwall is 70cm deep. And im in a 12m2 room (now when it is treated)
I also got panels made in MDF at the bottom of every basstrap. I don't think you can overdo it actually. But i always recommend consulting an acoustic architect before spending big money, that is what i did an my studio is awesome
__________________
-


studiohaga.net

Facebook
crillemannen is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 05:56 PM   #15 (permalink)
Soundlurker
Senior Member
 
Soundlurker's Avatar
 
Join Date: Nov 2005
Posts: 3,732
As mentioned, corner traps make a huuge difference in the low end. Regular 4-inch panels may remove some 100-150hz boominess, but good corner traps smooth out below that and they shorten the decay significantly. If you don't have any and your room is not of a more than decent size than you can be certain you have peaks and nulls of over a dozen or two decibels and the notes ring out too long making it even harder to judge what's going on.
__________________

Soundlurker is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 16th, 2011, 06:08 PM   #16 (permalink)
FloridaRolf
W.A.T.
 
FloridaRolf's Avatar
 
Join Date: Sep 2007
Location: Germany
Posts: 760
Quote:
Originally Posted by ::XeS:: View Post
What about the density?
Too dense materials may reflect (higher) frequencies
FloridaRolf is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old March 21st, 2011, 06:21 PM   #17 (permalink)
sprack
Thread Killer
 
sprack's Avatar
 
Join Date: Apr 2002
Location: Luleň, Sweden
Posts: 1,365
Certainly not cheap, but has anyone tried the Bag End E-trap?
It's an active trapping system.
http://www.bagend.com/bagend/ETrap.htm


sprack is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On





All times are GMT -5. The time now is 05:20 AM.


Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.0.0
© Copyright 2000-2014 UltimateMetal.com | MetalAges Media