Rigid foam is a great way to go. You can get anywhere from 1/2 in to 2 inch in 4x8 foot sheets. I have this on the exterior walls of my house and you can't hear anything. You would just need to make sure you or someone doing the project understands vapor barriers.
Has anyone used "Quiet Rock" sheet rock in room?
Has anyone used "Quiet Rock" sheet rock on the walls and/or ceiling in their listening room? I am building a new dedicated sound room and I am trying to do all the "small stuff" (i.e. clean power and a well built/designed/acoustically treated room). All input would be appreciated.