Using a simple Dynaudio SPL app on my iPhone, confirmed with Radio Shack digital meter, the background sound level in my living room with no music on and forced air system off, is 30db. When I listen to my system as background music, the level is 50-55db. When I sit down for serious listening, the level ranges from 60-75db whether source is digital or vinyl. I perceive this as close to levels I experience at various opera houses I've been to (Met, LaScala, Santa Fe, San Francisco), typically middle orchestra location, as well as performances at the various venues at Jazz at Lincoln Center. This sound level equates to 16x over the background level, though, according to various sources, perceived as 4x. What levels do you listen to and what is the dynamic range (meaning, does it exceed the 15db I experience)?