Same question turned around -- do you have the M3 in-walls actually mounted in the wall ? Not sure if they're sealed or open at the back so this might be a non-issue.

One other thing that's worth mentioning is that Energy C-3's are pretty nice speakers, and IIRC used to be almost 2x the price of M3's back when they were selling against each other... so if the M3's are sounding better than the C-3's you're doing pretty well IMO.

I would expect the C-3's to have better bass and to sound "bigger" than the in-wall M3's as a result -- I imagine you would need bookshelf M3's to get comparable bass -- but I don't yet understand why you're hearing the difference in soundstage unless the two speakers are mounted differently as well.

EDIT -- just saw your comment about the C-3's being $400 less than the M3's, so maybe $125 ?? IIRC C-3's were $500 US a pair back in 2002/2003 when the M3's were selling for a bit over $300, so sounds like you got one heck of a good deal.

Last edited by bridgman; 04/13/15 12:08 AM.

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