Audio room floor question

What about tile? Any soft surface, like floating wood flooring cannot be improved upon or "tuned" once installed. Yes, tile is hard, but is a good, solid, surface that can be "tuned" with area rugs to your liking. Nothing wrong with the raw stained concrete though for the same reason. You are on the right track with doubling up the sheet rock. You want a solid non spongy wall, and the floor is no different. I'd rather start with a solid, hard room that I could tune than with something already spongy.

Hifiharv....I might have to do as you suggest. The area lends itself to something durable like tile. we had to actually sink the room over 12" to get a decent ceiling height. I was looking at it with the contractor today and realized we didnt have any method to drain it if we had a burst pipe or some other mishap.

Before yo start just make out 2 inch deep and 4 inch wide grooves into the concrete floor to use it for future cable laying . Use cutter for making these gooves or chanels . I would buy aluminum rectangular chanels to lay them into the grooves and provide 8x8 inch opening at all places needed . I would say go for 12 mm plywood fixed on to the concrete floor and fix it to the concerete floor using screws. This will completely cover the floor and alu chanels are under the plywood . then over the plywood , lay solid hard wood about about 1/2 inch thickness and fix it using adhesive and very small headless nails . Provide 8x8 inch wood tile ( removable with easy lift ) at each opening for cable laying .
Do not varnish or wax the wood top surface , just use some mild oil and water to improve the look, but leave the pores open for good absorption.

Sorry , one thing forgot in my earlier post : First you need to put a thin palstic or polyethylene film on the concrete floor and then lay plywood over it. this will prevent any moisture seepage from the concrete floor.

(http://www.enjoythemusic.com/magazine/manufacture/0502/) The effects that are experienced while recording(do to floor bounce), will affect your listening room's presentation: (http://www.synaudcon.com/site/author/pat-brown/the-floor-bounce-effect-mic-placement-for-equalization/) You may find this helpful: (http://mehlau.net/audio/floorbounce/)