Hi Anonymous,

If you're running a subwoofer, I'd opt for "Small" so the sub assumes the duties of deep bass and lets the QS-8's woofers handle upper bass (from 100 Hz upwards) without the stress and potentially increased distortion that might occur if you selected "Large". Choose the latter if you aren't using a subwoofer. Listen to the results using both settings if you like, and make your decision on that basis, but I run my surrounds on "Small" (with a sub).

Regards,

Alan Lofft,
Axiom Resident Expert (Retired)