Notes: According to the liner notes if you don't have the finest high quality audio equipment, don't bother buying this record. I don't know if I'd go that far, but the electronic effects and tricked out pianos do lend themselves to a spacey texture throughout the recording. The liner notes are heavy into the recording equipment, techniques and methods as well as a nice bio of the players and a bit of their history together.F & T go upon a journey from oldies such as Greensleeves to such new concepts as The Man from Mars. Playing what sounds like every surface of the pianos, inside and out, the guys manage to bring it all together in their own unique fashion. The wonderful cover photo enhances the futuristic feel of the record. 

Here's some additional info from Scott W. Smith,  personal manager to Ferrante & Teicher:

Interesting sidenote...which you can include on this site: This was Art & Lou's 2nd prepared-piano LP. It followed "Hi-Fireworks" on Columbia Records. Soundproof was produced by: Dr. Kurt Liszt @ Westminster Records. Gimmicks include: wedges, chains, broken glass, wooden and masonite strips, rubber mutes, paper wads etc. Also included are the actual plucking, pounding and strumming of the interior strings! This LP included their first use of echo...sending the sound by wire to the floor below's tile bathroom...to speakers inside. Then mics were placed outside the bathroom door....looped to a delay and sent back upstairs to the mix room!! Echo "chambers" were not yet invented!