Audio room floor question

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.

Covering the floor entirely with carpet will be sure a much cheaper option compared to wooden floor . But acoustic will not be same . Also carpet is not a substitute for wall treatment and bass traps in corners , etc.
If one's budget is permitting , wooden floor will be better choice . But carpet would provide easy quick solution . IMHO .

Just one thing I can say : it is fine that you are going for concrete floor as I think solid rigid floor is better than floating one . Keep upper level of concrete such that in future , whenever your time and budget permits , you can just remove the carpet and put wooden floor of 3/4 inch thick on the concrete. S keep concrete level lower by 3/4 inch to take wooden floor in future , just in case! I find wooden floor ( plus small rugs) as the best for room acoustics .