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
This is a lot different than responses to similar questions as little as a year ago.

I love it when we get the usual tried it all and found only solid state is three dimensional.

What was your attending equipment? The rules have changed. Wires, preamps, and front ends have to be simple and wonderful. Over-sampling CDPs sound their selves flat and cranky. You just don't know that when matching them to solid state.

I am listening to the Beatle compilation, "Love, " and am freaking out!!!!!!!!
Crank them Skinnies Muralman1, the best Aps I ever heard, never forgot the hypnotic trance.
R times 8man

Thanks my man!! Ain't life wonderful? Pedal to the metal here......
I've reread Colloms's review and found another interesting point. Martin speculates (since he does not have enough exhamples of different applications of Class-D technology to prove his point), that the above avarage CI Audio resoult may be due to the liniar PS used in this amp. He observed, that switching on the amps with switch mode PS actually degraded the sound of the other system components connected to the same grid ! It may be (or may not) the reason why H2O amps sound superior to other ICEpower based designs that uses SMPS.
Very interesting thread. My take is that unbiased, objective evaluations of which class of amplification sounds better is impossible. Hearing, like all of our senses, allows only subjective evaluations to be made. It can not be otherwise! No two pairs of ears are created equal.

While poor design, component failure or bad system synergy can make any type of amplification unsatisfying, the preference for amplification type with relatively equal quality components is totally personal and not open for argument. To do otherwise indicates a complete lack of understanding of this subject or implies the existance of a hidden agenda.