Hi golfmonke,

When you are not using a subwoofer (you didn't mention one), then use the "Large" setting for all the speakers. If and when you add a subwoofer, then use the "Small" setting, as the decoder in your receiver will route all frequencies below 100 Hz to the subwoofer. This removes the burden of having to reproduce deep bass from the small woofers in the M3Ti, the VP100, and the QS4s. If you want, you can try the "Small" setting for the QS4s and see what differences you hear.

Regards,

Alan Lofft,
Axiom Resident Expert (Retired)