Panel thickness for dealing with SBIR .

[F1 fan]

For cosmetic reasons Im looking to build some wall mounted panels to replace the free standing ones that I now have behind my main speakers.I have a couple questions that I hope Brian or someone could help me with.The the front baffle of the speakers are 30" out from the wall and their is no possibility of moving them farther out into the room.

1)I suspect spacing is one factor but how else does one determine the required thickness of a panel for placement behind the speakers?

2) or should you just build one as thick as possible so that it is effective at lower frequencies?

3)how much wall area should be covered above and to the sides?(when looking at the panels from in front of the speakers)

Thanks in advance for your reply.


Fred

[bpape]

What does your FR look like without the panels behind the speakers and where do you have them crossed over at? Those 2 things will determine if you should build 1, 2, or 4" panels.

Bryan

[F1 fan]

Thanks Brian for the quick reply,at present I have no FR plots and they crossover to a sub at 60hz.

[atledreier]

Any news on this?

I'm thinking I'll put my corner traps in the corners, floor to ceiling, and 4" panels at front and side wall right up against the corner traps. That way I can 'hide' the fact my traps are pulled 4" out from the actual wall as well. Will that work or will it over-dampen the front? This is for music, by the way.

[bpape]

Again, it would depend on how close the speakers are to the wall, if you have a sub, if so, where is it crossed over, and what your frequency response looks like.

You'd probably be OK with 4" directly behind. How close are they to the walls on the side?

Bryan

[atledreier]

The rear of the speakers are around 40cm from the wall, and the side of the speaker is maybe 30cm from the wall. Too close, I know, but it works....

[bpape]

Yes - very close. I'd use 4" on the wall behind and 2" on the wall beside.

Bryan

[atledreier]

BTW, they are crossed over at 80Hz, and I have an SVS PB12+/2 doing the low stuff. The speakers are Dali Euphonia MS4, if that should matter.

[bpape]

And that's a good thing. My recommendations still stand. If you have good frequency balance between the mains and the sub, then all the more reason NOT to absorb too much below 80hz (4") that might actually 'unhide' a problem that's taking care of itself and just concentrate on what's being done by those speakers.

Bryan