How do Digital Amps Mfrs. compare in sound?

I am running the latest and top version of Nuforce, the Reference 9 V2SE. It is very wonderful accross the spectrum, particularly the bass and including the highs. The amp is reported to have high bandwidth, low distortion, near zero phase shift, a very high damping factor and a proprietary modulating signal versus Tri Path etc.

That said I can understand the difference of opinion about these amps. Using a tubed pre (Audio Horizons) my initial sound was amazing in the bass and harsh/glassey in the highs on 2/3 of CD's, noticeable at higher volumes in a very live room. I replaced my silver IC with gold and used Hyperion vibration control discs under the amps and voila! the highs are now sweet, extended and yet tame at high volume on about 80% of CD's. So the amps are sensitive to source material, wire, FRI, EMI, and vibration. They are also psychologically challenging. You hear this incredible extended articulate full bass and look down at the puny little things, knowing you paid less than half what would be usual for this good a sound, and it doesn't add up. But it is worth giving these amps a try. The detail, soundstage and musicality can be amazing if some time is spent on set up. Added to that is portability, low energy use, and space savings.

I agree completely with one thing that Stanwal said:

"I would have a long listening session with any of them before buying"

That is because switching amps -- which in most cases are analog devices and not digital) -- like any other technologies, have a sound that is much more characteristic to a manufacturer or an individual model than to a 'class'. Thus the sound can range from bright and distorted to exceedingly musical, from extremely extended to limited in bandwidth, from 'dry' to harmonically rich and complex, from quite rough to incredibly subtle.

It is worth pointing out that the HiFi Critic article is almost 2 years old and that at least 2 of the amps reviewed there are obsolete and withdrawn. Furthermore, From a logician's point of view, the negative inductive reasoning used by the author to draw his generalized condamnation is essentially flawed. . . there may be close to 100 switching amps on the market today. . . he examined 3 and declared them to be wanting, then glibly proceeds to condemn the whole lot, based on his spectacularly limited observations. On the other hand his guilty virdict -- had been most likely decided 'a priori'.

If the same reviewer were to examine with a completely open mind current production of leading switching amplifiers such as the newest bel canto Ref 1000 Mk.2, JRDG 312, and latest Spectron monos (just to name the very few I am most familiar with)(, he may discover that the art and science of reproducing music is not the sole prerogative of traditional -- and sometimes nostalgic -- technologies.

Returning to the original question, within the very limited scope of my experience, one of the highest values in amplification -- regardless of class and technology -- may be the very moderately priced current crop of Bel Canto monoblock amps: the Ref 500 Mk.2 and the Ref 1000 Mk.2. As for which variant of underlying chip set may be best. . . it is a question for which there is no particularly valid answer. . . to paraphrase and old cliche. . . "Tubes and chips don't make music. . . designers with tubes and chips make music!"

G.

Guidocorona, very astute mental clarity on your part! You answered my question regarding value point. I wonder if the Bel Canto Mk.2 upgrade carries over to the stereo amps?

Condocondor, I have no direct experience with the Bel Canto S500 stereo. Just looked at:
http://belcantodesign.com/new2008.html
By reading between the lines, it seems that the S500 may lack the input AC current rectification circuit of the Ref 1000 Mk.2 and Ref 500 Mk.2. I can only venture to guess that in the end the S500 may sound slightly less refined than its mono brothers. Yet, without direct experience, my guess has only the negligible value of the electrons you see on the screen to paint it. G.

The two that come to mind that offer UCD is Channel Island (D-200) and Kharma (MP150). The Kharma is a little more money then the CI. You can also go to hypex.nl, order the parts and build one yourself. I have a pair of custom UCD700 made to monos. These output 350 wpc into 8 ohms and 700 wpc into 4 ohms. I am now building another pair. My past amps are; Adcom, GAS Ampzilla, Dynaco ST-70 modded, Melos MAT-180 and Karan KA-i180.