How I built my bass traps...

[Cojo]

Hi!

There seems to be alot of talk about bass trapping on the board right now so I thought it was a good idea to post some info on how I built mine. I really want to encourage everyone to build their own, it's easy and well worth the effort!

Each trap is built as a 17 cm deep frame housing 15 cm (6") of rock wool (not the brand) then the front and back is covered with fabric.

Here is the material for the frame. You can also see four angled metal plates. They are there to prevent the rock wool from slipping out the back.

/Cojo

[Cojo]

Here is how they should fit together...

[Cojo]

Glue...

[bpape]

That'll work.

If you want to expose a bit more to the world, try drilling some holes in the sides, top and bottom.

Bryan

[Cojo]

...and screws.

[Cojo]

The finished frame! I'll post some more pictures tomorrow.

/Cojo

[Cojo]

Originally Posted by bpape

That'll work.

If you want to expose a bit more to the world, try drilling some holes in the sides, top and bottom.

Bryan

Thanks for you're advice! thumbsup

I've thought of doing that. How much more efficient would you think they will get?

/Cojo

[Poplab Studios]

thanks for sharing this

[pan60]

cool!

[Glenn Kuras]

Originally Posted by Cojo

Thanks for you're advice! thumbsup

I've thought of doing that. How much more efficient would you think they will get?

/Cojo

Well on a 4x2 4" panel it would give you 50% more exposed area if the sides are open.. 6"? well, check my numbers but that would be 75% more exposed would it not?

Nice DYI dude! ... You may want to think about putting some FRK on the fronts. This will help with a little more low end and also keep the room from going "DEAD" on the high end.

Glenn

[djui5]

Nice

[Bendybones]

Originally Posted by myfipie

You may want to think about putting some FRK on the fronts.

Thanks for this guys.
What is FRK?

[bpape]

FRK/FSK is a scrim facing that comes on some insulation products. It's paper on one side, foil on the other, and has a reinforcing mesh in the middle.

The purpose is two-fold:

- act somewhat like a damped membrane increasing absorbtion at a specific band based on the density of the material behind it.

- reflect upper mids and highs so you can absorb the bottom without overdoing the top and making it too dead.

Bryan

[Bendybones]

nice

[Cojo]

Originally Posted by myfipie

Well on a 4x2 4" panel it would give you 50% more exposed area if the sides are open.. 6"? well, check my numbers but that would be 75% more exposed would it not?

Nice DYI dude! ... You may want to think about putting some FRK on the fronts. This will help with a little more low end and also keep the room from going "DEAD" on the high end.

Glenn

You're right. I did the math and if I could fully expose the side, top and bottom the area would increase about by 80%! With the framing a more realistic figure would be in the 40% area. I didn't think it was so much. Unfortunatly these absorbers are allready done but I've allready plans for another batch so I probably make them with exposed sides.

Thanks for the advice on the FRK. Each trap is made of 3 slabs, I want them to absorb hi end aswell. What about putting FRK so it's facing the front between the first and second slab?

Thanks again!

/Cojo

[Cojo]

Originally Posted by Poplab Studios

thanks for sharing this

Anytime!

Originally Posted by pan60

cool!

Yep, thanks!

Originally Posted by djui5

Nice

To kind!

I'll post some more pics this evening!

/Cojo

[Bendybones]

Originally Posted by Cojo

if I could fully expose the side, top and bottom the area would increase about by 80%!

How do u mean "expose" them?
Do u mean expose the rockwool inside so that on certain sides it isn't covered by wood and heavy material?

[Cojo]

Originally Posted by Bendybones

How do u mean "expose" them?
Do u mean expose the rockwool inside so that on certain sides it isn't covered by wood and heavy material?

Yep, excactly! But it's hard to use all 80% because of the frame. So in round figures 40% would be more realistic.

/Cojo

[zoff]

Originally Posted by myfipie

Well on a 4x2 4" panel it would give you 50% more exposed area if the sides are open.. 6"? well, check my numbers but that would be 75% more exposed would it not?
Glenn

I'm using a frame made of 1'' by 2'' wood in the back of 2 2" 703 pieces.
Cloth is stapled to the wood frame holding the firberlass is place. This makes the frame much lighter and easier to hang. Is there any problem with building the traps this way?

[Cojo]

Ok, the frames are ready and it's time to get the insulation in place. I use a ground slab from Paroc. It's a very hi density mineral wool.

Here's a picture of the label.

[Cojo]

The open package.

[Cojo]

The first slab gets fitted. It's very tight and if you've done accurate messures it actually stay in place without any need to secure it. I've choosed to secure it anyway.

[Cojo]

First slab in place at the back, two more to go in front of this one.

[Cojo]

And here it is with all three layers.

[Joel DuBay]

Conny,

This is fantastic, and something the acoustic DIY community can benefit from in a big way.

There is s BRAND NEW Acoustics forum just about to go live that is non-commercial and is dedicated entirely to idea and application of DIY ACOUSTIC TREATMENTS..


Would you be interested in sharing your project at this new forum?

Please PM me, or email me through the website.
Your contribution would be enormous and greatlt, greatly appreciated.

Cheers,

Joel DuBay
www.readyacoustics.com

[Cojo]

Here's another picture of all four traps ready to get the final treatment! I'll post those pictures later.

/Cojo

[Cojo]

Originally Posted by zoff

I'm using a frame made of 1'' by 2'' wood in the back of 2 2" 703 pieces.
Cloth is stapled to the wood frame holding the firberlass is place. This makes the frame much lighter and easier to hang. Is there any problem with building the traps this way?

Hi.

If you have wood in the back of the 703 you can't distance them from the wall and they will not be as efficiant.

/Cojo

[zoff]

Originally Posted by Cojo

Hi.

If you have wood in the back of the 703 you can't distance them from the wall and they will not be as efficiant.

/Cojo

Thanks for replying. I hope I'm not hijacking the OP.

The wood is 2 inches wide and about 1.5 inches deep, so the 703 is 1.5 from the wall (I'm using these on the corners of the room).
Am I missing something?
Thanks.

[Cojo]

Originally Posted by zoff

Thanks for replying. I hope I'm not hijacking the OP.

The wood is 2 inches wide and about 1.5 inches deep, so the 703 is 1.5 from the wall (I'm using these on the corners of the room).
Am I missing something?
Thanks.

Aahhh... Now I see! Sorry, I had a hard time reading your sketch.

It looks fine! My mistake.

/Cojo

[bpape]

If you want them to do mids and highs too, then don't use any FRK/FSK. The point of it is to be able to do more bass control without overdoing the highs.

Bryan