Fabric wall coverings often ruin acoustic design despite being advertised as transparent

Evidence

Loudspeakers and acoustical treatments are sometimes not very attractive, and so it is common to stretch fabric over large portions of walls. This is not a problem if the fabric is acoustically transparent, but many are not, including some advertised as such, in which cases a lot of careful design, and the sound of the room, are degraded when the “finishing touch” is added. — Toole, Floyd E, Sound reproduction- the acoustics and…, 1437

Categorization

• CANDY: A fun, tweetable gotcha: decorative fabric covering walls, the ‘finishing touch’, quietly destroys meticulously engineered acoustics.
• SEED: Article angle: the war between aesthetics and acoustics in room design, and how decorative choices silently undo engineering.