Tweaks when building a listening room?

The number one rule is "broadband absorption' - keep the acoustic treatments even. If you have floor to floor carpet then you may already be ok in the mids and treble from the get go. Then all you need is large thick bass broadband absorbers and plenty of plush furniture. See my virtual system example for what you can do with a fireplace. There is such as thing as too much mid and treble absorption - so keeping the room lively may actually make it sound better. It is pretty much impossible to overdo treatments in the bass - so do as much as you can aesthetically handle...