I’m more that a bit curious about the same M700 and M1200 attributes: size, empty space, and mass.
In one way or another I believe Paul may have addressed all three in his videos but one leaves me a bit skeptical.
In one video Paul addressed a senders question about why amps cases are so empty. His response basically said size is a hold over from rack dimensions. Many have chosen to shrink the cases (maybe those with no full size history?) while others, including PSA, elected to stay full size. Okay fine.
Related to space and size is the question, why mono blocks? There seems to be lot of room under the hood (at least the M700), especially if a 2ch module spec’d. Paul addressed this in another video saying mono blocks are better than stereo, but only marginally better than dual mono, for isolating channels / power supplies. Okay fine, I’ll buy that.
I’m having a difficult time with mass, which I think Paul may have also addressed in a video. In the video he recounted preparing to hop a flight to Asia to attend an audio show. His distributor called in a panic telling Paul to stay home because they couldn’t show the amp because it didn’t pass the knock test. To pass the test they scabbed a steel plate to the cover and all was well.
I look under the hood of a M700 and I say 13 pounds is a bit much but okay, ya gotta have some heft to it.
The M1200 at 27 pounds is what I’m having a hard time accepting. Is this all marketing mass or is there some legit reason the M1200 should weight so much?
Scroll down until you see the interior photo and then start reading. I think you will find a decent explanation.
One question for you: Why are you concerned with the weight? To me, 27lbs doesn’t seem to be an issue.
Many thanks. I hadn’t come across that review. Besides offering other helpful insights to VTV and Benchmark amps on my radar, it did address my question/skepticism about weight.
My only concern about weight is that the contents of the box didn’t seem to justify the weight. So the cynic in me was drawn to conclude that marketing is capitalizing on a consumer correlation of quality to weight to justify a price. The more it weighs the more you can charge, even if the added weight doesn’t bring sonic benefits.
I don’t know how vibration affects amplifier performance but I’ve seen enough references to it to conclude an argument can be made for mass and isolation.
I probably wouldn’t hear the affects of vibration or many other subtle differences by themselves. But, unless it’s all just total BS, I can rationalize that their cumulative effects could reasonably result in an overall improved listening experience.
And this in a nut shell is a my conundrum. Call it FOMO but in choosing components I want to settle on those that are most capable within budget of contributing some perhaps subtle benefits, even if they’re not at first obvious.
If mass and isolation are a couple of those subtleties then I’m willing to accept that mass has justifiable sonic benefits, though I will always remain a bit skeptical that marketing has something to do with it.
In Class A and A/B amps, metal mass is needed for heat dissipation. Otherwise the output devices would let the magic smoke out quickly and possibly very violently.
Class D, not really…so damping the chassis against vibration is the only reason for mass. In an M1200 where there is a tube, this is critical to keep microphony out (a sometimes VERY audible and annoying phenomenon).
The M700…I don’t know. The purist in me wants everything dampened. The cynic in me says I can’t tell the difference. Plenty of tiny class D amps on the market from reputable manufacturers say that the cynic is correct. Having said that though, I own the 700s 
Excellent point. Thank you. The above referenced reviewer experienced microphony due to a partially unseated tube. So damping vibration is especially relevant.
Another advantage of weight—resistance to moving when pushed. Simply turning my NAD FM Tuner on/off can make it slide (even though it is on the same “rubber” blocks as the rest of my kit (PSA M70os, GainCel Dac/Pre, and Perfect Wave SACD Trans). Heft works.