Most cost effective room treatment?

You must damp all first reflections, even the AES standard room assumes that these are damped. I enjoy ASC traps very much, and they're as "cost effective" as most anything in this hobby, if indeed anything is so. I also augment secondary and complex reflection points with a few RPG profoam pieces, and two Echobusters panels.

Try carpet and curtains first. The improvements are not subtle. I recently changed from a light weight curtain to an extra light weight curtain. I immediately had bad reflections all over the 12 X 20 room. It sounded like a room before you move in the furniture. Before putting out extra cash make sure the basics are in order. Good luck.

1) Buy a house with a bigger room ! There is truly no substitute for a large room with high ceilings and heavy non-vibrating construction. I used to have one, and I miss it. 2) If you have a television, or even your audio racks between the speakers, you might want to try and move them to the side. Get them into an acoustically quiet area where the sound from the speakers won't shake up the equipment as much. I found huge improvements when I moved all my TV stuff out of my audio room. 3) Get rid of your coffee table, or put some sort of damping material over it. I had a large one with a reflective top. I tried removing it and found that I had better sound. 4) Tie your power cables together and route them down one side of your rack. Space your interconnects and run them down the other side. 5) Offset speakers at an angle to the wall so they don't have a flat surface to creat a standing wave against. 6) If you have a reflective wall next to the speakers, put something non-reflective at the point where the sound will reflect.

Hire me to design your room for you! Erik 323.697.4134