class d

At HE2007, I listened to two systems with Bel Canto REF1000 and S300 amps. The sound from both of these systems was a bit grainy on top. There was enough bottom slam, but it wasn't as clean and tight as some other tube and ss amps at the show. The systems were totally different for each amp, but these qualities were consistent for some reason. This finding was quite surprising to me as I was expecting the BC amps to sound clean, articulate and fast, based on impressions from reviewers and other users.

In the end, I ended up getting the Spectron M3 SE. After 5 or 6 months, I got another one and set them up in balanced mono-block configuration. I couldn't be happier with my choice.

iSanchez

Are there any Class D preamps? If not, are there likely to be any in the near future?

Never say "never", but I've not seen a Class D preamp and don't expect to. Class D is a method of producing high power with low heat, compact size and low weight. Since preampss are low power devices, the advantages of Class D are not really needed, at least in audiophile applications. Maybe in car audio, has anyone seen a Class D head in a car audio system?

Dave

08-03-08: Coffeey
... I've listened to two different class d amps,and they didnt sound to bad,but just didnt pull me enough to pursue further so i sold them,it does seem they are quite promising.

With the disclaimer that I've not auditioned class D amps in any formal manner, I've read a lot and gotten some sense of concensus. The only two class D amps I've come across that consistently collect favorable reviews, eliciting descriptions such as "smooth," "musical," and "involving" are the range of PS Audio amps and the modest little Onkyo A-9555 integrated amp.

The Onkyo lists at $700 but is easy to find under $500. Both Stereophile and The Abso!ute Sound gave it enthusiastically favorable reviews. The only thing that has caused me to hesitate buying one is that it has no pre-outs, and I might like to bi-amp. The reviews of the Onkyo also mentioned that it had excellent bass extension, tight bass control, and excellent yet musical clarity throughout. Yet its damping factor is a mere 25.

This PS Audio overview of their GCA power amp series mentions that their first-gen HCA-series amps of this topology only managed a damping factor of 25-30 as well. So that makes me wonder if switching amps manage to assert tight control without a measurably high damping factor. Still, the overview also mentions that for their new GCA line they figured out how to up the damping factor considerably.

Despite what one may read, Onkyo and PS-A are not in the elite class of ICEPower or Class D. They're good value for the money, but not really top contenders. PS and Onkyo have significant marketing budgets that garner them many reviews vs. the boutique makers with little or no budget.

Dave