Need advice on how to sound insulate my room

Need advice on how to insulate my stereo room. My rig is is in the finished basement of my home. Problem is that the house is old'ish and the sound reverberates throughout the house - probably through the basement drywall and ceiling.

The upstairs floors are hardwood, with throw rugs. The walls are plaster on lathe.

The basement ceiling is drywall. However, the ceiling height is only about 8 feet, so a drop ceiling is not an option.

Not sure there's much I can do, but any suggestions have to be aesthetically nice or my wife will object.

Thanks