Mounting my panels today

[solchild]

Hi ive finally built my panels and will be mounting them today.
I was thinking of mounting them with an air gap between the panel and the wall for the side walls for first reflections. I have 2" 703 panels and Im thinking about going with a 2 inch wall gap.

What exactly will mounting the panels with a 2" gap do? I imagine it would make the panels more efficient but I havent had confirmation.

Your help would be greatly appreciated.

thanks in advance.

[Jens Eklund]

http://www.gearslutz.com/board/5999249-post4.html

[DanDan]

Very broadly speaking it will double the effect.
It is nearly as good as doubling the thickness.
Absorption will be effective for about an extra octave downwards.
The airgap really is a free lunch.
A bigger airgap would include dessert. No harm in 3-4 inches if you can afford the space. Angles can be good too.
Lighting placed behind such panels is a great 'look'
Got me on the front cover of Mitch Gallaghers book..
Acoustic Design for the Home Studio
DD

[seen-da-sizer]

Originally Posted by Jens Eklund

http://www.gearslutz.com/board/5999249-post4.html

Would love to see a chart with 100mm rockwool-no air, as a comparison to 50mm wool - 50mm air.

[solchild]

Originally Posted by DanDan

Very broadly speaking it will double the effect.
It is nearly as good as doubling the thickness.
Absorption will be effective for about an extra octave downwards.
The airgap really is a free lunch.
A bigger airgap would include dessert. No harm in 3-4 inches if you can afford the space. Angles can be good too.
Lighting placed behind such panels is a great 'look'
Got me on the front cover of Mitch Gallaghers book..
Acoustic Design for the Home Studio
DD

Angles? how do you mean?

[DanDan]

Most people mount traps parallel to the wall or ceiling. There can be advantages to angling them. This is getting a bit sophisticated but there can be a useful improvement. Consider a side reflection control panel. View it's reflection in the ETC graph. Angle it and see what happens.

Here's an online Absorption calculator.
You can try combinations of gap and different Gas Flow Resistivities.
Porous Absorber Calculator

100KG Rockwool would be about 50000 Rayls.

Huge collection of other GFR figures here Common Gas Flow Resistivity numbers.

DD

[localhost127]

Originally Posted by solchild

Angles? how do you mean?

there is a longer path through the insulation (effective thickness of absorber) as angle of incidence moves away from normal (0*; perpendicular to the absorber). however, as you approach 'grazing' angles, absorption will decrease significantly:

http://www.gearslutz.com/board/7165515-post44.html