Class D Technology

I'm very curious about Class "D" amps. No I've never heard one. How does Class "D" compare to SS? I'm a tube guy who has not heard the very best SS amps, but I did hear an ARC SS that I didn't like.

If a person prefers SS to tubes in general, his opinion is less valid to me, than someone who prefers Class "D" over tubes or claims that he can't tell the difference.

I've been told that for watts of power, class "D" is cheaper; that's nice, but I don't have a serious power problem, just curious.

My tubes have a black background; I know this is not supposed to be so, but current tube equipment has achieved that. Maybe not as Black as Class "D", and yes, there are levels of Blackness.

While the quickest way to find the answer to these questions is to buy one; that is not an option. I hope I've arranged my questions in an order that won't offend anyone, but will get an answer to the best of their ability in regard to Class "D"

The new Wyred  SX 1000R mono's sound great. They replaced the great Vitus RI 100, 13k retail. 6moons review pretty much on. Nothing beats big power if it is decent.

No I’ve never heard one. How does Class "D" compare to SS? I’m a tube guy who has not heard the very best SS amps

We, most are all in agreement that Class D is great in the bass. To me where they differ mainly is in the upper mids and highs, some saying there’s hardness up there, and others saying there’s missing information that causes larger then usual gaps between notes creating the "illusion" of a blacker background. I call it an opaqueness.

The different sound of Class-D especially in the upper mids/highs, comes down to how close to the audio band the mandatory output filter on all Class-D’s is bought down to get rid of the class d’s massive amount of VHF switching noise.

If bought down low to erase most of the switching noise, this intrudes into the upper frequencies of the audio band. Which makes it very smooth but robs most of the harmonic structure of the mids and highs, this "could" be compared to tube or class A s/s smoothness.

If it’s not bought down to low it lets quite a bit of VHF switching noise through, this maintains the harmonic structure of the mids and highs but also adds a certain hardness to the sound of class-D

To me the only way to cure this comes in future semiconductor component development, which will allow the switch frequency to be set 5 x higher, so the the output filter can be set much higher as well so then do it’s job properly to get rid of all the switching noise without effecting any of the audio band at all. Then they’ll also be able to drive full current even down to 1ohm from 20hz to 20khz, instead of today falling off a cliff below 4ohms.

Technics have a >$30k amp the they developed with their own components to get the switch noise up 2 x as high as anyone one else, a step in the right direction, but it needs to be higher again 5 x the norm today. They still do not include a 2ohm wattage figure in their specs, as it would still show limitations.
http://www.technics.com/us/products/r1/se-r1.html
When that day comes we’ll all be using them and our heavy, hungry, hot tubes and SS, will become boat anchors.


Cheers George

If bought down low to erase most of the switching noise, this intrudes into the upper frequencies of the audio band. Which makes it very smooth but robs most of the harmonic structure of the mids and highs, this "could" be compared to tube or class A s/s smoothness.

My class D amp has 60kHz -3dB bandwidth. Georgelofi - you must be a bat?

George you conveniently forgot to mention some think the sound including the high frequencies are quite good and not flawed.  

Lets not selectively filter feedback just to help make a case.   

Im listening to my Bel Canto C5i Class D integrated with Triangle Titus speakers currently.  Other than the clean articulate bass I could easily think the amp was a very resolving and clean and dead quiet tube amp.  The treble is as good or better than most anything I have heard.  The sound draws you right in. 

So so let's stop trying to convince people the technology is flawed or does not sound good.   It's as good as anything these days done well.   Done well is the key like with any technology old or new.