Owens Corning TheaterBoard & SelectSound

[archive]

From: "Steve Guidos" <sguidos@n...>
Date: Fri Jan 28, 2000 5:31 pm
Subject: Owens Corning TheaterBoard & SelectSound

I was looking around for Owens Corning 703, which has been mentioned here a
bit, and which I've also read about here and there. It seems that 703 is a
good choice for sound absorbtion, I assume because it's relatively cheap and
easily obtainable.

I couldn't find any at my local national-chain hardware stores, so I called
the Owens Corning 800 number, and after several voice mails and 3 different
reps I finally located a local building supplies dealer who can get 703. In
the process, Owens Corning suggested I check out their "Theater Board" line
which comes in a 'black mat', and also their 'SelectSound White Acoustic
Core' which is supposed to be similar but white (for better asthetics when
covered in colored cloth). The 'Sound Absorbtion Coefficient' of the
SelectSound and the TheaterBoard are better than the 703, in fact the spec
sheet lists the following for 2" thicknesses:

703-ASJ TheaterBoard SelectSound
125Hz .47 .25 .20
250 .62 .73 .74
500 1.10 1.08 1.12
1000 .81 1.11 1.07
2000 .51 .99 1.05
4000 .32 .99 1.04
NRC .75 1.00 1.00

I have a small recording studio, and the vocal room has a resonance around
2.4K, so the specs would seem to indicate that TheaterBoard / SelectSound
would be better for me. But sometimes specs aren't worth the paper they're
written on...... So my questions:

1) What does 'NRC' mean above?

2) Has anyone used either TheaterBoard or SelectSound, or know anything
about it in the 'real world' compared to 703?

3) What about cost-effectiveness? The price I have on TheaterBoard and
SelectSound in 2" thick 2x4 sheets is around $1 per square foot.

4) I am thinking of 'doubling up' the boards in the corners of the room to
help control bass; as I understand it, 4" would trap much more bass waves
than 2". Is this correct?

Steve Guidos

[archive]

From: Brian Marston <marstonb@z...>
Date: Fri Jan 28, 2000 9:35 pm
Subject: Re: Owens Corning TheaterBoard & SelectSound

Steve Guidos wrote:
> From: "Steve Guidos" <sguidos@n...>
> I was looking around for Owens Corning 703, which has been mentioned here
abit, and which I've also read about here and there. It seems that 703 is a
good choice for sound absorbtion, I assume because it's relatively cheap and
easily obtainable.

703 is about 48 to 50 kg / cubic metre. This, amongst other factors,
gives it good low frequency performance.
>
> I couldn't find any at my local national-chain hardware stores, so I called
the Owens Corning 800 number ... <snip> ... Owens Corning suggested <snip>
"Theater Board" <snip> 'SelectSound White Acoustic Core' <snip> The 'Sound
Absorbtion Coefficient' of the SelectSound and the TheaterBoard are better than
the 703, in fact the spec sheet lists the following for 2" thicknesses:
> 703-ASJ TheaterBoard SelectSound
> 125Hz .47 .25 .20
> 250 .62 .73 .74
> 500 1.10 1.08 1.12
> 1000 .81 1.11 1.07
> 2000 .51 .99 1.05
> 4000 .32 .99 1.04
> NRC .75 1.00 1.00

With a bit of adjustment for the foibles of testing they look about the
same from 250Hz up.
Your 703-ASJ values looks like the performance of a "faced" construction
(not raw 703). NRC of 0.95 (not 0.75)

> I have a small recording studio, and the vocal room has a resonance around
2.4K, so the specs would seem to indicate that TheaterBoard / SelectSound would
be better for me. But sometimes specs aren't worth the paper they're written
on...... So my questions:
> 1) What does 'NRC' mean above?

NRC - arithmetic average of the absorption values across the mid-range
(250,500,1000,2000)
A rough guide only to the performance of the material. The roll-off
indicates that these are lighter (less dense) materials than "703"

<snip>
> 4) I am thinking of 'doubling up' the boards in the corners of the room to
help control bass; as I understand it, 4" would trap much more bass waves than
2". Is this correct?

Full depth better is than doubling up.
Two layers of 2" may be only slightly better than one layer of 4".
If you are doubling up 4" make sure the layers are rough side to rough
side.