I had listed my 8400's for sale as they weren't doing it for me anymore, but now after I added foam under the ear pads, I have to say I might reconsider. The added bass is really welcomed and in turn reduces the too prominent highs. I think there's more treble than bass and midrange with this headphone, so much so that the headphone sounds overly bright and thin. After adding the foam (from a Grado pizza box) the sound came more into focus. Bass guitars had body, bass drums had kick, and the whole sound was smoother and fuller. The mids also came forward a bit.