I'll get to the point quickly. I liked these amps even more than it sounded to me that Mark Mickelson liked them (to which DAS responds with a !!!! because he figures Marc liked them a LOT). I think these are among the very best sounding amplifiers available at any price. They have a musical ease and correctness that is hard to appreciate until you have heard it. These amps offer the best of solid state and the best of tubes. They have powerful, dynamic and deep bass. The highs are extended and pristine with no hint of solid state or tube related problems. The midrange has the organic wholeness that you get from good tube amplifiers yet is clearer and less distorted and less colored than any tube amp I have ever heard. The M-70s possess enough power and dynamic capability to amaze you when used as the main front right and left power amps in a surround system. Movie soundtracks like 'Terminator 2' can bring lesser amp to their knees. But the M-70s hung in there like no 70 watt amp I have ever heard.
Since the M-70 amps were developed primarily with classical music as a reference, I was certain that they would wimp out on more energetic forms of 'big' music like large scale rock, electronic music, and dense dance/trance mixes. But nothing flustered the M-70s. In fact they sounded better doing this 'big' music than my 200+ watt reference amp.
$5,600 is serious money for an amplifier and you have a right to expect something special at that price point. The M-70s are indeed special. If you have heard touted solid state amps before but were unimpressed by the sound... you'll know what I'm talking about when I say the M-70s are not like that. If you've listened to expensive tube amps and thought, "How can you learn to live with compromised bass and treble performance just to get that midrange?' You'll find the M-70s have what you want AND what you missed. I could go on and on about this, but you just have to hear it to understand.
I was able to improve the sound of the M-70s to a surprising degree with two add-on products. I tried many others but the M-70s seemed to be unimpressed with other products/tweaks. This could well mean that considerable attention has been paid to getting the M-70 very well 'tweaked out' which will make the owner's life a lot easier later - not so many things to worry about trying. My first recommendation is to ALWAYS listen to the M-70 monos using a Bright Star Air Mass air bladder isolation platform and a Bright Star Audio Big Rock damping platform (they stack with the Air Mass on the bottom). These 2 products turn amazing amps into unbelievable amps. You can get an Air Mass 2 and Big Rock 2 (be sure it has the new larger top plinth with no foam around the edges) and fit both amps onto one Bright Star stack for around $350. If you prefer placing the amps near each speaker, consult with Bright Star (firstname.lastname@example.org) about appropriate sizes for the 9.5' wide x 22' deep amps. Barry makes a Big Rock specially for the Cary 805 mono amps that looks to be very close to the right size for the Clayton amps.
The next successful upgrade was the change to Audio Power Power Link Power cords, 6' for about $159. These sounded quite a bit better than more expensive power cords in my system/room. But there were not as big an improvement as the Bright Star isolation/damping system. Nevertheless, I never want to hear the M-70s with the stock power cords again. What the Power Link cords do quickly becomes something you can't live without. Bass improves, clarity improves and silence/transparency improves.
What can I say to get you excited about these amps? They REALLY deserve your attention if you are lucky enough to be able to shop for amps in this price range. But Clayton has no gimmicks. The Clayton folks are not professional hucksters. They are not over-hyping themselves. In fact you would hardly notice them if it weren't for me trying to reach out of this web page to shake you around a bit to get you to listen to these amps. Geez these are good amps! With the 2 tweaks in place you have $6,250 invested in an amplification system that just may be unbeatable at any price - you might equal the M-70s' performance with other products, but not at that price.
These are not amps for show off audiophiles. They sound too good and too natural. Nothing is zipped up and hyped-out to make people notice how special your system is. Sit a music lover in front of a good system driven by these amps and they will be beside themselves. These amps don't make bad recordings unlistenable. They don't artificially improve bad recordings either. You hear what is there without distraction - unenhanced and unsympathetic. This is a rare thing. Too many top-of-the-line amps make less than perfect recordings either very difficult to listen to or impossible to enjoy. You will not be so limited with the Clayton amps. But when you do put on the very best recordings... well, I, uh, don't know what to say again - I don't want to cliche you to death. I have never heard better sound in my listening room than what I got with these amps in the system.
What about speaker cables and interconnects to use with these amps? Oddly, many wires seem to work well. Some do some things better than others. With just one exception, I found myself without strong preferences one way or another. The makeup of the rest of your components will probably have more to do with the wires you finally select than the amp itself. I had great luck with inexpensive DH Labs Silver Sonic T-14 bi-wire speaker cable (silver plated copper, Teflon insulation, twisted pair with outer jacket). Cardas Cross sounded very fine, more dimensional with a little more distant perspective. XLO type 5 was lively and dynamic. Nothing to dislike about any of the wires, yet none of them screamed out this is the perfect wire! either. As always, experiment a bit. I did hear one combination that just did not sound right at all though... the JPS Labs speaker cable and interconnect. These are known to perform well in other applications, but they didn't cut it with the Clayton amps.
I hope you understand just how stoked up I got about these amplifiers. The M-70s are something special that deserve your attention. If there's one thing you should remember about my Clayton M-70 follow-up, this should be it:
Click Here for Marc Mickelson's full Clayton Audio M-70 Review