I'm not salesman, just a senior audiophile and I have decided in recent months that I'll never go back to conventional AB
amps since its prehistoric technology going back 50 tears. The subject here is currently the worlds finest Class D amp in its price range and beyond, right behind Patrik Bostroms' massive Class D Marten M amplifier. I wouldn't waste my time with Brunos' Mola Mola Kaluga, since the Nuprime technology is newer and has moved further on. The Evolution One has technology that is a first in the industry. Ten years ago, the real problem with Class D amps and today as well, is that their transistor switching modulators operate at a frequency around 300khz which is to low causing feed back problems to the upper frequency's resulting in cold hard sound from the tweeter. Brunos' Kaluga switches at 500khz which is still not good enough, resulting in the Evoultion One being the only Class D amp in the world to switch modulate at 700khz. Also, the only Class D amp on the market with an input impedance of 1 million ohms. Phew! So the issue of working with different Preamps is redundant and completely irrelevant and will work perfectly with any Preamp on the market, tube or solid state. Their switching amps are custom designed in house and are patented. For those concerned about speaker 2 ohm impedance loads read the recent review in Totally Wired where the Monitor Audio Studio's were used and are 2 ohm loads and the amps ran cool. Also, legendary circuit engineer Demian Martin from Spectral has been an ongoing consultant for the company. 



" Demian Martin is way above Nelson Pass as a design engineer. "
In what specific ways ?


As far as I know the Evolutions were broken in and the outcome was more musical so that is why the change was made.

Happy Listening

facten...I only trust what I hear. I mentioned earlier that I once owned the X-1 Preamp that was a factory reburb. Absolute mint when I received. The price was really low. Paid $ 2500.00. At the time I also had Parasounds former flagship the PLD-2000 and the Parasound HCA-1500 amp, Since the X-1 was already burned in, my impressions weren't that great during the three weeks I owned the piece and sold it for $3K. The X-1 was warm and relaxed, but the Parasound was much faster, more dynamic, with a larger sound stage. The X-1 was not even close to the Spectral DMC-10 I listened to years earlier, lacking that very rich, very smooth velvet midrange  that is all to rare from a solid state. The DMC-10 dynamics and sound stage were excellent as well. teajays' recent thread on the Coda 07x preamp that it surpasses the earlier Spectral models is a bold statement, but doesn't surprise since Eric Laachi was on the design team with Nelson Pass at Threshold for years as we all know. If I had to choose between Coda and Pass Labs? Coda hands down.
@bigkidz...what preamp was your friend using with the Evo's ?
Off to the hospital to have my second hernia surgery. Get back to you great people in a few days...Cheers