Yeseco products are acoustically effective. No airgap is needed behind them. They are measured at VTT (Finnish National Test Laboratory) according to EN ISO 3565 / EN ISO 11654 standards. All our wall acoustics are of the best sound attenuation class A, and Still T reaches the best in class weighted sound absorption coefficient aw 1,0 which implies best possible 100% sound absorption in the class.
The acoustic properties of Ilmava products depend on their installation. In the wall installation, the sound gets through the panel and bounces back from the wall thus getting twice through the product. The acoustic characterisctics are then the same as those of fabric covered wall mounted Yeseco producs. In the free space installation, the sound gets through the product only once and the achieved attenuation is different, but now both surfaces absorb the sound and the absorption area is doubled.
Yeseco products are 45 mm thick, but people ask for thinner products. The test report includes measurement of a 30 mm thick product to demonstrate the general negative impact of the product thickness to the sound absorption and the increased amount of the thinner product. The measured Sound Absorption of 30 mm thick Still T aw 0,8 means that sound Absorption as such is good. However, after reading our pages yu cas see that you need it more than twice as much than 45 mm thick products.