john you have also suggested me great about same subject in homerecording/bbs. i am now planning to build it in real and here are some initial thoughts:
1. Ceiling: Drwall and Glass fiber inside
2. Wainscoting: Glass fiber+ pegboard
3. Floor : Carpet
Doors should be sealed off according your contruction guide with weatherstripping around.
soundlock
Originally posted at johnlsayers.com, topic 208.
Mate - I think Steve at HR answered your question as much as can be answered according to your questions.
cheers
john