[WildWolf]

I am building a 12' X 6'6" X 12" riser. I would like to turn this into a bass trap. In order to turn it into a bass trap, I will be adding vents to the back of the riser. I am also building a 4" riser on top of this one just for the seats. This second riser is where the vents should go. Should I leave the back of the 4" riser open and have the vents there? Is there another way to do this? Thx

 

[WildWolf]

nobody???? What if I start the 4" riser 4-6" away from the wall and cut vents into that 4-6" area? Will that weaken the plywood too much? I am putting my row of 4 chairs on the 4" riser. Will this work? Am I not describing this clearly? Thx

 

[Lindy0026]

My understanding, (which is some degree of partial,) is that you use the open cavity of the riser, which is filled with fluffy fiberglass insulation, to absorb the sound energy of the bass. Therefore, you would want your 12" riser doing the absorption, not the 4" one. When I built the riser in my room, I used a layer of 3/4" plywood, roofing felt, 1/2" plywood, roofing felt, 3/4" plywood. two full inches of plywood is solid as hell. cutting vents in it won't weaken it.

 

[HopefulFred]

Have you seen this thread? There's lots of good how-to sort of talk here - especially where granroth posts his results. linked here: http://www.avsforum.com/forum/19-de...tion/1527200-risers-101-a-6.html#post30087402

 

[WildWolf]

My understanding, (which is some degree of partial,) is that you use the open cavity of the riser, which is filled with fluffy fiberglass insulation, to absorb the sound energy of the bass. Therefore, you would want your 12" riser doing the absorption, not the 4" one. When I built the riser in my room, I used a layer of 3/4" plywood, roofing felt, 1/2" plywood, roofing felt, 3/4" plywood. two full inches of plywood is solid as hell. cutting vents in it won't weaken it.

Thanks. I am only using 3/4" plywood on top.

 

[WildWolf]

Have you seen this thread? There's lots of good how-to sort of talk here - especially where granroth posts his results. linked here: http://www.avsforum.com/forum/19-de...tion/1527200-risers-101-a-6.html#post30087402

I am reading it now...thank you!