Sound proofing / tightening up a room

I need a little help with sound proofing a room. Well not so much sound proofing but my drum sounds aren't tight enough, ill take pictures and post them , its the corner of a room. Its 3 walls and a massive open space, and its carpet over cement... ive heard plywood is good for underneath a drum set? what else would help? Click on the studio link in my profile and see if you can hear what im talking about...
Thanks
 
i used 4" mineral wool fiber because it is actually more dense than the 4" owens fiberboard(this is what the guy at spi said. he claimed the mineral wool is 8lbs density and the four inch owens was 6 lbs density). i built six traps for under a hundred bucks and they work great. i just bought the mineral wool and then went to a fabric store and got some cheap fabric. i then "gift-wrapped" the 2x4 foot mineral wool with the fabric and some safety pins and put them up it the corners of my cr and i have two extras for either the live room or whatever. it took all of 20 mins to "make" them. they look good and perform even better. i cant reccomend this enough if you are looking for the best cheap solution.
 
just remember that these homemade baffles will help with high end a bit and deaden the room. But if your looking for bass management, which i think is just as important if not more so, then you will need specific bass traps to help to tame low end problems.