Fibrolite

[Vytis]

Any thoughts on absorption figures?

[Sebg]

Fibrolite is relatively inefficient as an acoustic absorption material. If you want dust-free, see if you can get polyester absorption batts - similar to these:

Acoustic Insulation
Polymax - Office & Retail
Autex - Acoustic Insulation, Wall, Ceiling, Reverberation Control, Reduction, Acoustic Fabric

The Tontine Acoustisorb and the Martini Polymax Absorb have finer denier fibres (edit: finer than other polyester products such as pillow and furniture filling) so have reasonable flow resistivity.

Cotton-based products will still produce dust. I don't know about the Hemp products but acoustically I expect it would be better than the Fibrolite.

[kasmira]

A coefficient of ~.10 until 1.5k is next to NO absorption. This stuff looks un-useable for ANY sort of bass trapping. I doubt 10 of these would do anything in your room other than act like carpet. I assume your local dealer is thinking that acoustic properties for broadband absorbers are similar to those used to reduce STC when implemented inside wall cavities, which is honestly hardly similar at all. I would recommend against it, unless you have some odd problem frequency at 1.5k which I don't really see possible if you have other traps. IMO, a better idea would be to wrap the traps in plastic.

[Vytis]

Thanks for your input, Sebg and kasmira! I truly appreciate it!
The dealer offered to send me a free sample sheet of 50mm thick Fibrolite along with my order for a pack of hemp insulation. If their hemp proves to be almost as good as my rockwool panels, I will replace everything with hemp to keep my studio clean.
Many thanks once again.

[sandersd]

Originally Posted by Vytis

I will replace everything with hemp to keep my studio clean.
Many thanks once again.

Just don't tell any of the musicians the studio is filled with hemp...