[tasar]

Danny........could you share the PCF and Absorption numbers of your No Rez ? Also, is this product available in different thickness ? Further, do you happen to know if the foam is a poly(ester) (ether) form of urethane and if the backing is a vinyl composite ?

[Danny Richie]

The foam layer is open cell, flexible polyester based, urethane foam.

Density and absorption values was not a primary focus to the design. It was very much secondary and not all that relevant as other materials like fiberglass insulation or polyfill are intended to be used with it.

All of the testing was for resonance control of MDF. The damper chosen is a viscoelastic compound of various materials.

It is only available in one thickness.

[tasar]

Thanks Danny. Anyone using it as a membrane, in conjunction with "fiberglass and polyfill", as you imply ?

[Danny Richie]

Thanks Danny. Anyone using it as a membrane, in conjunction with "fiberglass and polyfill", as you imply ?

What do you mean by a membrane?

[tasar]

in general, a working layer of a bass absorber

[AKLegal]

No rez is not a good bass absorber for a couple of reasons.  The foam layer is not dense enough to work as a thin panel absorber.  Likewise, while the foam layer is about as dense as say fluffy pink fiberglass, it is not thick enough to be as effective.  Lastly no rez is expensive even when compared to expensive varieties of Owens Corning 702, 703 etc. 

But maybe you mean using it to make something like this?  http://www.gikacoustics.com/gik_scopus_tuned_traps.html

I think the damping layer is probably flexible and stretchy for that application.  You would have to pull it really tight to get it to resonate and then you would have to test it to see what frequency it resonates at because the trap would only be effective at that frequency.  Also note that the absorption layer should not touch the membrane, so you would have to strip the foam layer away from the damping layer.

However, no rez when used as directed on speaker cabinets will have a profound affect on bass quality.

[MarvinTheMartian]

Tazer
You should probably google "mass loaded vinyl"
http://www.primacoustic.com/maxtrap-science.htm

Our own AC "Acoustics Circle" is a good start point

These guys can be a bit more extreme ...
http://www.gearslutz.com/board/studio-building-acoustics/

Shawn

[tasar]

Danny........so, "No Rez" was purpose built strictly for damping ? Does this supplier do other acoustic attenuation, such as bass trapping MLV or VPR foam ?

[Danny Richie]

Danny........so, "No Rez" was purpose built strictly for damping ? Does this supplier do other acoustic attenuation, such as bass trapping MLV or VPR foam ?

The manufacturer will make anything you want so long as you order enough of it.