I have a Parasound Halo A21 and a 7125, and I am quite happy with them both. They are in different systems running different speakers, so it's hard to compare the sq. I think the A21 gives a better soundstage and better resolution of mids and highs, though that could be the other gear in the chain speaking. The class A operation for the first 10 watts is nice, as are the looks. IMO, you can't go wrong with either line depending on your budget and needs.
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Home Theater: Epson 8100, Onkyo 876, Outlaw 7125, Oppo 103, Speakers: Paradim Monitor 7, cc370, Totem Lynks x 4
2 Channel system: Oppo 95, Parasound Halo A21, Halo P7, Paradigm Signature S6
Bedroom: NAD C326BEE, Panasonic S97, Tannoy Revolution DC4, Energy Classics