California Fire Codes (the quilts must be non-burning under a 30 second flame) (alum works) or wool.

DUST - The quilts will certainly clear the air - but who will clean them twice a year?

Read Mossberg's or Leo Laport's visitation to a modern Disney/Spielberg Sound Studio. Big foam blocks (hundreds and hundreds)that could be moved throughout the outer edges of a 150 piece orchestra to create the correct pickup for dozens of mics.