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.
elberoth2
Class-D has tons of potential. I think the Gilmore Raptor's sound fantastic. I have also heard great things about the Spectron sig. He mentioned price was not an issue, but the more expensive Class-D amps do sound much better.
Woodburger and Bbro have said it. Synergy is where it is. I have found naked speaker cables make night and day differences. Same goes for non-oversampling. The preamp choice is paramount as well.

As class D amps continue their spread, we will see cable and preamp builders bringing out more great class D friendly gear.
"NuForce, when does not need to drive difficult load which it can't, doing admirable job too."

My Nuforce's have zero problems driving my Aerial 10T's and they are certainly not what I would consider an "easy" load.
I was not a fan of class-D amps untill I heard the H20 Signature monoblocks. They changed my mind.
I agree that Class D amps have a lot of potential. We have only scratched the surface of this new technology. It may not be quite there sonically yet but it is getting closer, and according to some as stated above, it is as good or better than conventional amps. There is a lot to be gained in terms of size, efficiency, cost, etc. And don't forget that some amps with conventional output stages have been designed with switch-mode power supplies.