My audition of the Spectral DMA-80 left me with mixed impressions.My prejudices in home music systems should be mentioned, before launching into adjectives that have no useful reference point.
Current amp is a Bryston 3B NRB into a passive Mod Squad preamp. With XLO and MIT cables, this rig drives older 18 inch box speakers (Infinity QEs with EMIT tweeters). I've found that these speakers gradually roll off bass under 100hz, but driven by the Bryston the bass and lower-mids are a strong presence. I consider my system gives me exceptional bass and dynamic responsiveness, a very involving sound even with digital.
The DMA-80 is an extraordinary amplifier. It immediately transformed my system from one which had a slightly grainy and non-blooming treble to the opposite: a spacious highly detailed upper mid and treble.
Extraordinary detail. The transformation was so startling that I was immediately relieved of the suspicion that my Theta Pro Basic II was responsible for lack of air and refinement on top. No, indeed. Well-recorded piano such as on Stan Getz' "Serenity" truly shone. One could not ask for more. Soundstage was excellent and more laid back than with the Bryston. Each musical line was more clearly separated and articulated, yet still in sync with other musical lines.
The let-down came in with bass impact and dynamics. Bass lines were severely softened. Dynamic contrasts and dynamic sensitivity were less than through the Bryston -- mainly in the bass, but noticeable across all the ranges. The little nuances of volume changes were a bit less. Emphasis notes that I'd grown accustomed to as sign posts, were not as firmly emphasized.
Once I discovered and brought into my conscious mind my bias, I have to admit that I cannot seriously consider any component that detracts from dynamic impact in comparison with my current system. However no question, the Spectral is a must-audition for those concerned with mid-range and treble beauty and transparency, for in those areas it is fabulously gifted.

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I don't know how you came to acquire a Spectral product, I did it because of the sound, period.
I could listen to the thing for days with NO listening fatigue whatsoever, just like you can listen to an actual musical instrument.
After owning it for 7 years, for some insane reasons, I decided to sell it. After it was gone I realized how good it really was and how practically IMPOSSIBLE it would be for me to find a better sounding amp, shorter of buying another newer Spectral. The amp just performs so amazingly and flawlessly that it disappears in your listening environment. I think that the reason for selling it was just that, for a brief period, I stopped focusing on the music and shifted my attention to equipment: BIG MISTAKE!
Am I here to kiss Keith's and company's asses? I don't think so. I don't buy the bullcrap of the $5000 MIT cable set, but I do think that spectral rates among the five best audio manifacturer in the world and number one in my book. The DMA-80 is a perfect example of how great spectral products are.