OK, I hate to post this, because I really want to deny it for my own sanity. However, I think the QS4s (at least my tis) tend to sound a little congested when you're playing music with a bunch of bass through them. T
Who plays bass through the surrounds?
That's what the subwoofer is for (i.e., the .1 channel).
There should not be any bass sounds mixed for surrounds in DD/DTS or dvda-sacd material, though perhaps you are referring to music bass notes while using a DPLII or a similar DSP?
The QS4s and 8s are the same speaker, only different size.
I second Bridgman's notes on the topic.