Excellent questions Bernard, let me try to address them
You are correct about the inherent sonic/musical limitations of old amplifiers based on the past generation of ICEpower modules. Without a lot of work from the amp designers, ICEpower ASP series modules invariably yielded sterility.
NCore NC1200, and a few other new generation modules, are completely different creatures. In my own experience, even simple NCore NC1200 implementations, such as the Merrill Veritas that I have reviewed for PFO at
http://positive-feedback.com/Issue68/merrill_audio.htm
exhibit a degree of musicality and control of intermodulation distortion which is rare in amplifiers of any technology.
I have listened to M825 at some length at RMAF 2014 over three days. I used my standard test CD that I have been using for all auditions during the last 7 or so years Grand piano; string sextet with double bass; Diana Krall with her band; Symphonic; vocal ensamble + sax in a cathedral, Anne Sophie Mutter on violin with orchestra . There was no audible trace of any harshness in the treble, which would have been the tell-tale sign of intermodulation sidebands. Neither multipart treble sostenutos of high strings, woodwinds, high brass, or fff transients showed any sign of ever breaking apart . There was never any hardness nor shrillness, just exposed harmonic complexity.
Compared to M925, I could not detect any M825 degradation of staging and images, which would have been the sign of cross-talk leaks.
You are correct If your Amati speakers are not bi-wirable, part of the benefit of adding a second M825 unit might be lessened.
I have owned M625, M725, and M925 I comfortably prefer M925 over M725 for every conceivable audible parameter. Conversely, I found M725 to be somewhat closer to M625, although I still prefer M725 over M625.
The difference in frequency response between M725 and M825/M925 has no bearing on any audible parameters of music reproduction . The sonic/musical advantage goes to M825/M925 by a significant amount.
Traditionally, amplifiers with very high damping factor have shown a propensity of generating hard cardboardy bass . Not so NCore based amps The bass resolution of M825 and 925 is controlled in the sense that it has no wooliness or pillowing, but it is deep, correctly fast, and filled with harmonics starting at the fundamental . Do not be concerned about M825s high damping factor.
Class D designs do continue to evolve, and so do other class of operation . However, while class A and A/B designs, with some exceptions, seem to be evolving relatively slowly, The underlying technology in some class D amplifiers have recently performed a quantum leap in inherent musical performance Of course, to experience the absolute magic they are capable of, one needs to have the patience to go through a lengthy break-in process, as I have outlined earlier on this thread.
Bottomline.... M825 and M925 are phenomenal amps in the absolute sense... , Hope this helps... Let me know if you have more questions,
Guido
You are correct about the inherent sonic/musical limitations of old amplifiers based on the past generation of ICEpower modules. Without a lot of work from the amp designers, ICEpower ASP series modules invariably yielded sterility.
NCore NC1200, and a few other new generation modules, are completely different creatures. In my own experience, even simple NCore NC1200 implementations, such as the Merrill Veritas that I have reviewed for PFO at
http://positive-feedback.com/Issue68/merrill_audio.htm
exhibit a degree of musicality and control of intermodulation distortion which is rare in amplifiers of any technology.
I have listened to M825 at some length at RMAF 2014 over three days. I used my standard test CD that I have been using for all auditions during the last 7 or so years Grand piano; string sextet with double bass; Diana Krall with her band; Symphonic; vocal ensamble + sax in a cathedral, Anne Sophie Mutter on violin with orchestra . There was no audible trace of any harshness in the treble, which would have been the tell-tale sign of intermodulation sidebands. Neither multipart treble sostenutos of high strings, woodwinds, high brass, or fff transients showed any sign of ever breaking apart . There was never any hardness nor shrillness, just exposed harmonic complexity.
Compared to M925, I could not detect any M825 degradation of staging and images, which would have been the sign of cross-talk leaks.
You are correct If your Amati speakers are not bi-wirable, part of the benefit of adding a second M825 unit might be lessened.
I have owned M625, M725, and M925 I comfortably prefer M925 over M725 for every conceivable audible parameter. Conversely, I found M725 to be somewhat closer to M625, although I still prefer M725 over M625.
The difference in frequency response between M725 and M825/M925 has no bearing on any audible parameters of music reproduction . The sonic/musical advantage goes to M825/M925 by a significant amount.
Traditionally, amplifiers with very high damping factor have shown a propensity of generating hard cardboardy bass . Not so NCore based amps The bass resolution of M825 and 925 is controlled in the sense that it has no wooliness or pillowing, but it is deep, correctly fast, and filled with harmonics starting at the fundamental . Do not be concerned about M825s high damping factor.
Class D designs do continue to evolve, and so do other class of operation . However, while class A and A/B designs, with some exceptions, seem to be evolving relatively slowly, The underlying technology in some class D amplifiers have recently performed a quantum leap in inherent musical performance Of course, to experience the absolute magic they are capable of, one needs to have the patience to go through a lengthy break-in process, as I have outlined earlier on this thread.
Bottomline.... M825 and M925 are phenomenal amps in the absolute sense... , Hope this helps... Let me know if you have more questions,
Guido