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Do ClassDAudio Amps Have Proper Decay Of Notes?

I'm interested in the ClassDAudio kits. Has anyone tried them? I had a tripath amp once and it had a liquid, detailed quality that I liked but it was too fast with the decay so ultimately sounded a bit fake, even with a tube pre. Full-bodied, lush, but too fast. I've heard the Hypex modules from Holland have nailed the decay issue but they're miles out of my price range. Just wondering if the ClassDAudio kits are close in terms of decay.
uberdine
georgehifi's avatar
georgehifi
10,312 posts
 

BTW: that "future" much higher switching frequency I talked about above, is closer than we think.

Technics with their SE-R1 are showing vision by developing their own much fast switching frequency transistors, double the norm that’s around now. It would still be better if it were 5 to 10 times faster, but it’s small steps to a good end for Class D. Then you’ll see me sell my big hot power hungry boat anchors.

But the amp is expensive at around $22,000.00usd I believe.

http://www.technics.com/us/products/r1/se-r1.html#overview

And you can bet they’re not going to sell those transistors to just anybody.

Just one reviewers words of what he heard:

"Listening to tracks that we’ve heard 100s of times — and on excellent systems at that — is now a revelation of once hidden nuance and detail. Not only are we hearing things we’d never heard before, we’re hearing it in a way we’ve never heard it before. A music system that sounds like a live performance is a tough goal to attain, but Technics’ flagship nails it."

Cheers George

m-db's avatar
m-db
970 posts
 
Class D has evolved into many different iterations. Since my first switching amplifier, the PS Audio HCA-2, I've owned four other brands and auditioned in house six others. During this time I had an Ayre V-1xe, MFA D75, and Carver VTA 180s on hand.

Nothing personal but I guess I'm just skeptical when I read about generalizations regarding switching amplifiers. While I've seen graphs that dramatize a digital waveform I honestly can't hear anything that would suggest a stair stepped waveform or "digital noise" from any of the switching amplifiers I've listened to. Early on I would admit to there being a difference in presentation but I've been fooled by the NuForce SE's and the nCores in short term listening in my own system.  The only commonality that I've found in most class D designs is their sensitivity to the quality of AC power and poor synergy with silver cabling. If memory serves me the Hypex nCore kits were $1300 direct.

The nCores are in my studio system driving a pair of Avalon Acoustics Monitors. The combination is stunningly transparent which is amazing for monitoring my recording but not exactly ideal for casual listening. Over the long term I prefer my VTA 180s driving the Eidolons in the main system, but thats me.      
atmasphere's avatar
atmasphere
11,778 posts
 
While I've seen graphs that dramatize a digital waveform I honestly can't hear anything that would suggest a stair stepped waveform or "digital noise" from any of the switching amplifiers I've listened to
Just so we are clear here, class D is not digital. Its an analog process.
georgehifi's avatar
georgehifi
10,312 posts
 

Yes as Ralph has corrected about class D classification not being digital.

Also the "digital noise" I believe is an analog switching noise and is around 600-800khz, too low to be effectively completely filtered out of the audio band without effecting it with early hf roll off.

The new Technics SE-R1 with their new proprietary transistors takes this switching noise up to 1.5mhz which is a step in the right direction.

But from those in the know the switching noise needs to be up around 3-5mhz to make the filtering completely effective, and not to intrude into the >audio band at all, then it will take Class D into proper hi-end amplification.

That’s when I’ll sell my hot inefficient heavy boat anchors and also go Class D, and the smart linear amp manufactures will have their fingers on the "sell my business button" before this this technology comes along for anyone to source these new super fast transistors, or compete with the Chinese.


Cheers George

m-db's avatar
m-db
970 posts
 
["Just so we are clear here, class D is not digital. Its an analog process."]

Absolutly.

I believe there was one self described "Digital" amplifier but I can't recall the brand. I didn't refer to any class D amplifier as digital.  Some reviewers have used examples of stepped digital waveforms to describe or imply what the typical, or some, switching amplifiers using pules width modulators are outputting. 

My QSC PLX 2400 Bass rig amplifier has a switching power supply that makes a hell of a mechanical noise but it can't be heard in the output. I may be getting too old but unless we're talking about substantial difference in the amplifiers basic presentation I have yet to hear any class D amplifier produce switching noise.


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