Class-D amps - a different re view


Martin Colloms, the editor of HiFi Critic (ad-free mag from the UK) have recently published the review of several different Class-D amps, together with an in depth technical analysys and measurments.

His conclusions were not favourable, to say at least:

"I regret that not a single model merits unqualified recommendation. Price is not the issue; the poor listening tests speak for themselves. (...)
At present we have to take the prudent view that good sound might be possible from switching amps, but we haven't heard it yet."

BelCanto REF1000 (ICEpower) - score 10.5 pooints
"The ICE power module used has a dependable reputation, and the design is well built and finished as a whole. While I would not suggest that you shouldn't try this amp, on sound quality grounds alone I cannot recommend it for audiophile use."

Channel Islands D100 (UcD) - score 13 pooints
"While I have reservations about a number of aspects of sound quality, and advise personal audition, given the solid lab results (...) the overall performance and the moderate price, these CA Audio monos do make it to the 'worth considering' cathegory."

NuForce 8.5V2 (proprietary technology) - score 9 pooints
"Yes, the price is good for the power output. Yes it's pretty, light, small and runs cool. However, the sound quality simply does not justify recommendation." (on top of that the NuForce amp measured very poorly - Elb)

Pro-Ject Amp Box (Flying Mole) - score 5 points
"I'm sorry to say that Project (...) was a real disappointment in the listening tests, and can't be recommended."

Just as a point of reference, recently reviewed Krell 700CX scored 100 points, CJ Premier 350 - 110 points and ARC Ref 110 - 135 points.

At least someone have had the balls to say it. This is why HiFi Critic is THE mag to subscribe.
128x128elberoth2
high muralman:

i prefer the vintage tube sound. the conrad johnson mv 125 is my favorite amp. no class d amp will resemble the mv 125.

a class d amp will never sound like a vintage tube amp.
I suppose it would be blasphemy to bring up the Carver Conrad Johnson shootout of the 80s...
>>10-31-07: Mrtennis
a class d amp will never sound like a vintage tube amp.
Mrtennis

10-31-07: Dazzdax
Mrtennis: And a vintage tube amp will never sound like a class D amp
Dazzdax<<

Wow, this is really deep thinking. Maybe you guys should take the MENSA test.
Hi Atma, I do grant you that these show hotels seem to have lucky spaces and very very unlucky ones. Trying to Tame the wildness of some suite I am sure must be a frustratingly thankless task. . . . perhaps as easy as herding cats?! Is one of the problems that you manufacturers end up having to select a room from a floor-plan without having the opportunity of sonically testing the space ahead of time? Perhaps RMAF organizers should be encouraged to assign some of the odder sounding rooms to the admittedly few static displays. . . do not need good acoustics to select LPs from a bin, after all.

Back now to the discussion of artifacts and stereotypical audible flaws in switching amps, without here pointing fingers to models/brands in particular, I observe that that there are a number of such amps today that do still sound stereotypically 'digital' to a slight or greater extent. Among 'non stereotypical' switching amps, I have already waxed poetic on this and other threads about the two switching amps that I truly like as of the end of 2007. I should also point out though, that I have heard switching amps that did not seem to have any audible 'digititis', and still I was not able to like. In one particular case, the sound of one seemed overly dark to a fault, almost if the designer were attempting to overcompensate for expected stereotypical flaws. not sure if I was having a bad audio moment or I was perhaps in a 'dark' sounding suite. I did discuss the device with other audiophiles that have listened to it under various circumstances and received confirmation of my cursory impression.

As you said, the switching technology is young and evolving rapidly. It's certainly worth watching with an open mind. It is equally true that it may in the end turn out into the proverbial flash in the pan. . . and 10 years from now, instead of having grown to broader maturity, it may be simply remembered as a valiant experiment. We will have to wait and see.