Best Cheap Amps for Magneplanar Speakers

D-Sonic.  Should be in your price range per channel, and are very powerful.  I had my MG-12s "gunned", and that's what John "Peter Gunn" recommends.  He also recommends Butler and Sanders, but both are out of your price range per channel.  Butler is tube, just an fyi.

If you can swing the upgrade, do it.  John is not sure how much longer he will be doing it, and to the best of my knowledge he is the only one out there with such offering.  You get awesome looking handmade wooden frames, top notch crossover parts and sound that is out of this world.

Tell him the mad russian send you.  He'll probably charge you extra :-)

www.d-sonic.net
http://www.indiespinzone.com/magnestand.html

The Bryston 4 series has been mentioned a few times.  It should be noted that this was the "de facto" recommendation for Maggies back in the day; from Magneplanar themselves and from Lyric Hi Fi, the biggest Magneplanar dealer at the time (80-90's).  This was the "affordable" amp recommnedation for many years.  Having said that, while the store demos using Bryston sounded good, they never sounded nearly as good to me as the demos using tube amps.  I can't help but notice how often the term "to drive" is used without, imo, enough emphasis on the quality of the resulting sound.  Sure, something like a large Adcom and many affordable ss amps will "drive" Maggies well and provide plenty of output and decent bass (maybe), but the sound will lack refinement and finesse.  While the ultimate dynamic range may be wider than with a moderately powered tube amp, on a micro dynamic scale the sound that a decent tube amp can produce within a narrower dynamic range may have a better sense of aliveness and excitement; not to mention the possible advantages in the areas of timbre and dimensionality.   

I have two options I use to feed my rebuilt 3.3rs:  (1) Krell KAV 250A for "daily" (non-focused, i.e. sitting at my desk doing other chores) listening -- also has the advantage of not putting out much heat; and (2) Rogue Audio Magnum M-120 monoblocks, for more serious listening and when I am in a tubey mood.  The monoblocks tend to heat up the room after a couple of hours.

There's a Krell for sale now.  Rogues come up every so often.  

I really enjoy both - the Krell offers a lot of control and the Rogues add a lot to the fun factor.  

Ditto the Bryston 4BST, an improvement over their original design. I’ve been driving both Martin Logan reQuests and Dahlquist DQ10’s and it hasn’t skipped a beat. I think it’s a ’dual monoblock’ design, and you can usually find ’em at about $1G if you shop around.

I own Maggie 20.1s.  I first powered them with an Accuphase P1000 SS amp.  On paper, the Accuphase was the perfect amp.  It was capable of delivering lots and lots of current, 1000 amps into a 1 ohm load!!  The Maggies are a 4-5 ohm load, and that meant about 200-250 watts to that load.  The sound was good, but not great.  Very clean, quick, but not to my ears musical.  I replaced the Accuphase with a pair of Manley Neo Classic 250s.  EL34 tubed amps at 250 watts into an 5 ohm load.  Much more musical than the Accuphase.  The music had more sole, the soundstage was very realistic.  I agree with Frogman, tubes bring out the best in Maggies.  Oh, and I wouldn't hesitate to get the 60WPC Quicksilvers unless you like ear splitting sound levels.