Vertical Banners / Blinds

What are vertical acoustic banners?

Vertical acoustic banners (or blinds) are mainly used to flexibly provide sound absorption in spaces (i.e. make them less ‘echoey’).

They can either be:

hung and extended along hard vertical surfaces (walls, windows, etc) to absorb sound and reduce the sound reverberation (i.e. ‘deaden’) in the space. Their length can be adjusted depending on how much sound needs to be absorbed. Or;
rolled away, sometimes in a dedicated casing, to increase the sound reverberation in the space.

Vertical acoustic banners with adjustable length (right)

The banner systems are usually mounted on walls at high level or on soffits.

Vertical banner systems are usually motorized and include either one or two layers of textile.

Flat acoustic banner systems with one and two layers of textile

What materials are vertical acoustic banners made from?

The acoustic banners are usually made with seamless and porous textiles such as:

wool serge
encore velour
synthetic velour
polyester
wool

The weight of the materials ranges from approximately 0.1 kg/m² to 0.6 kg/m² and some materials can be flame retardant.

What are the sound absorption characteristics of acoustic banners?

The sound absorption of acoustic banner systems range between Class C and Class B sound absorption.

It generally increases with the number of banners (See graph below).

Sound absorption coefficient of one and two flat banners (polyester, 0.53kg/m²) in front of a hard surface [1]

With textile being a porous material, acoustic banners are better at absorbing sound at mid and high frequencies (from 500 Hz) than at low frequencies (below 250 Hz). Although, the sound absorption can be increased at low frequencies if the banners are installed within a niche [1] (See graph below).