I've been reading quite a bit about bass traps and am a little confused by all the differences. Two designs in particular I've been looking at are the completely sealed like Ethan Winer's and the semi-sealed like John's.
http://www.johnlsayers.com/HR/index1.htm
http://www.ethanwiner.com/basstrap.html
Does anyone have experience with the differences? I'm trying to figure out which one is better suited for my needs. I have a basement with 7'3" ceiling (that's to the bottom of the floor joists where I plan to fill w/ 703) & I need to do something about the bass response/overall sound. It won't be a square room... maybe 15x12 at the large area... not symmetrical. The purpose of the room will be for a practic studio and also to do some live recording. I know it's not the best room, but it's all we have at the moment.
My original plan was to build a version of Ethan's, only angle the front panels for diffusion, and I was going to make a "triangle" trap to fit in the corner similar to John's, only air-tight... but I'm curious about the slatted design too.
Any input or links to any other designs/recommendations would be greatly appreciated. I've been searching on several message boards and it's hard to find one post that compares different designs/benefits.
many thanx
Differences Between Bass Trap Designs?
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dymaxian
- Senior Member
- Posts: 357
- Joined: Tue Dec 02, 2003 7:21 am
- Location: Madison, Wisconsin
The slat absorber works on a very different principle than the panel trap does. The slat absorber is meant to be a Helmholz resonator, which works like a soda bottle does- it resonates at a particular frequency, and the insulation inside converts some of the resonant energy into heat (miniscule amounts). The panel trap theory uses the air inside a sealed box as a spring- outside the box, low-freq sound pressure waves vibrate the front panel, which makes the air inside vibrate, and again the insulation inside converts some of the energy to heat.
They both work very well. I've read in a couple places that panel traps are easier to tune for lower frequencies (perhaps because a sealed box takes more energy to vibrate than a helmholz resonator) but they both do the job.
If you know, from testing it, that your room has a couple of problem frequencies, then you can try to tune a couple absorbers to absorb them. If not (it sounds like not, from your post) then your best bet is to build a bunch of different kinds of absorbers, for as many different frequencies as you can, and try to absorb over as much of the sound spectrum as you can.
Building a corner panel trap will work just fine. In fact, it'll probably have a very deep center frequency compared to other panel traps because it'd have a greater volume than a flat-against-the-wall kind that Ethan has designed.
Hope this helps!
Kase
www.minemusic.net
They both work very well. I've read in a couple places that panel traps are easier to tune for lower frequencies (perhaps because a sealed box takes more energy to vibrate than a helmholz resonator) but they both do the job.
If you know, from testing it, that your room has a couple of problem frequencies, then you can try to tune a couple absorbers to absorb them. If not (it sounds like not, from your post) then your best bet is to build a bunch of different kinds of absorbers, for as many different frequencies as you can, and try to absorb over as much of the sound spectrum as you can.
Building a corner panel trap will work just fine. In fact, it'll probably have a very deep center frequency compared to other panel traps because it'd have a greater volume than a flat-against-the-wall kind that Ethan has designed.
Hope this helps!
Kase
www.minemusic.net
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delphonic
- Posts: 5
- Joined: Wed Mar 31, 2004 5:40 pm
thanx kase...
I'm aware of how the two work (in theory), but I'm also looking for real-life experiences and what people have found to work the best. I'm thinking about trying both.
My biggest problem with the slat variety is that among all my searches it's hard to find a good set of construction details. I keep seeing references to "John's design," but haven't seen it. If they're referring to the setup on the front page - that doesn't seem to give much detail. If there's a link to someplace that has more info please let me know. I'm still searching trying to avoid posting the same questions as many other newcomers.
...but here's a few anyway I'm trying to get figure out.
-I haven't seen much for length & width of the overall design (only depth).
-I've seen mention of different slat & slot widths on the same frame - how are different sizes arranged?
-does the insulation touch the panels?
Any links to more info would be greatly appreciated.
thanx!
m@
This was the idea. Right now I'm just trying to get the overall sound under control. When I have the time/resources I'll do a more stringent analysis of the room.dymaxian wrote:...your best bet is to build a bunch of different kinds of absorbers, for as many different frequencies as you can, and try to absorb over as much of the sound spectrum as you can.
I'm aware of how the two work (in theory), but I'm also looking for real-life experiences and what people have found to work the best. I'm thinking about trying both.
My biggest problem with the slat variety is that among all my searches it's hard to find a good set of construction details. I keep seeing references to "John's design," but haven't seen it. If they're referring to the setup on the front page - that doesn't seem to give much detail. If there's a link to someplace that has more info please let me know. I'm still searching trying to avoid posting the same questions as many other newcomers.
...but here's a few anyway I'm trying to get figure out.
-I haven't seen much for length & width of the overall design (only depth).
-I've seen mention of different slat & slot widths on the same frame - how are different sizes arranged?
-does the insulation touch the panels?
Any links to more info would be greatly appreciated.
thanx!
m@
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dymaxian
- Senior Member
- Posts: 357
- Joined: Tue Dec 02, 2003 7:21 am
- Location: Madison, Wisconsin
Well, that link on the front page seems to have all kinds of detail... what additional details are you looking for? The height dimension is just whatever you need for your room.My biggest problem with the slat variety is that among all my searches it's hard to find a good set of construction details. I keep seeing references to "John's design," but haven't seen it. If they're referring to the setup on the front page - that doesn't seem to give much detail. If there's a link to someplace that has more info please let me know. I'm still searching trying to avoid posting the same questions as many other newcomers.
Kase
www.minemusic.net
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delphonic
- Posts: 5
- Joined: Wed Mar 31, 2004 5:40 pm
I didn't see any references to height or width of overall design, or if they matter... in relation, does it matter how long the slats are (i.e. in a 4 foot design can they be four ft or is it better to have a stud down the middle - effectively making them 2 ft).
It seems you can vary the range by using different sized slats/spacings, but I haven't found a good resource on HOW you combine these different sizes/spacings. i.e. if I'm using 2, 3 and 4 inch slats, how are these spaces in reference to eachother?
These are the types of details I haven't found good resources for. If one is inexperienced with the design it's hard to know whether these are a factor unless it's otherwise noted.
Thanx for the replies!
m@
It seems you can vary the range by using different sized slats/spacings, but I haven't found a good resource on HOW you combine these different sizes/spacings. i.e. if I'm using 2, 3 and 4 inch slats, how are these spaces in reference to eachother?
These are the types of details I haven't found good resources for. If one is inexperienced with the design it's hard to know whether these are a factor unless it's otherwise noted.
Thanx for the replies!
m@