I have a sense of deja vu--that I already answered a direct email question from you but perhaps not. By the way, the term "rear surrounds" (even I use it) is a misnomer. Dolby Labs specify that surround speakers be mounted to either side of the listening area, not at the back, except for the genuine rear speakers used in a 6.1 or 7.1 setup. QS multipole models are accommodating enough that you can mount them almost anywhere and achieve an enveloping soundfield but I feel they're at their best located to the sides of the listening area, somewhat higher than ear level. They don't need to be wall-mounted. The enveloping soundfield provided by QS surrounds is much easier to achieve than with direct radiators like the M2 or M3.
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