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When did class D start to not suck?

voodooless

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Is that enough of a example?
You think those are class H? How?

Class G and H are about modulating the power supply of the amplifier. Clearly these amps don’t do that.
 

solderdude

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Class D = an amplifier that switches the output devices really fast between positive and negative rail. The analog signal, a bit like DSD in that sense, is obtained using an LC low pass filter. Very efficient in power.

Class G = non switching amplifier (usually class A or AB) with several (more than 1) different power supply rails. The sole purpose of this technique is increasing efficiency, heat. Carver PA amps worked that way decades ago already. Small rack sized amps with huge power and little cooling needed.

Class H is well.. kind-off a class G variant. The difference with class G is that while class G has more than 1 power rails (so in 'steps') the class-H amp has a (switching) power supply that creates an internal voltage rail (actually 2, 1 positive and 1 negative) that does not switch (like class G) nor is constant (A, AB) but is modulated (when voltages above a certain voltage) are needed and thus always is just a few volt higher than the required output voltage.
The advantage is even higher efficiency than class-G. Almost on par with class-D.
Normal class AB (or even class A) amps can be created with these techniques while wasting of heat is reduced (higher efficiency)

class G and H are not related to class-D but the rail voltage modulation is switching so class-D-ish.
 
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ZolaIII

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You think those are class H? How?

Class G and H are about modulating the power supply of the amplifier. Clearly these amps don’t do that.
Some people like to call their designs class D in H bridge for example Hipex but don't get confused it's H class inherited design with what ever they put in and for what ever reason they want to call it class D which is wrong.
 

abdo123

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Class D = an amplifier that switches the output devices really fast between positive and negative rail. The analog signal, a bit like DSD in that sense, is obtained using an LC low pass filter. Very efficient in power.

Class G = non switching amplifier (usually class A or AB) with several (more than 1) different power supply rails. The sole purpose of this technique is increasing efficiency, heat. Carver PA amps worked that way decades ago already. Small rack sized amps with huge power and little cooling needed.

Class H is well.. kind-off a class G variant. The difference with class G is that while class G has more than 1 power rails (so in 'steps') the class-H amp has a (switching) power supply that creates an internal voltage rail (actually 2, 1 positive and 1 negative) that does not switch (like class G) nor is constant (A, AB) but is modulated (when voltages above a certain voltage) are needed and thus always is just a few volt higher than the required output voltage.
The advantage is even higher efficiency than class-G. Almost on par with class-D.
Normal class AB (or even class A) amps can be created with these techniques while wasting of heat is reduced (higher efficiency)

class G and H are not related to class-D but the rail voltage modulation is switching so class-D-ish.

And what is your opinion on the unnecessarily heated discussion over semantics?
 

Calleberg

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Probably before you were born. 1976.

Sony TAN-88:
View attachment 225489

Yes, thats a SMPS and yes, they're VFETs in a Class D design. Yes, it's a die-cast block of alloy making up the chassis. It weighed only 11kg, put out well over 160wpc@8R, S/N over 110dB, distortion curve flat from 10W to nearly 180W.

Bruno Putzeys was only three (3) years old when it was sold.

But surely theres is/was a catch right?
Otherwise this would have been a Classic everyone would have known about, and I don't think it is.
 

sq225917

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Class g and h are power supply descriptions, applicable to any class of amp. You can have a class d amp with linear power supply or a smps.

Seems like you're a little muddled.

A class d amp uses a pwm switched output, that's the definition of the class, it doesn't include psu considerations.
 

boXem

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Yes they are mixed DC (analog/digital) integrated circuits on the bord and independent systems as such and of course RF part will remain analog for example. That's called SoM (system on module) this day's. It's contained of SoC (system on chip) with additional regulation elements and PCB for it. Which all of those are. Of course when we talk about solid state class AB we see it as independent transistors (MOSFET's, GREC's...) and not anything tighter integrated.
Seams I nead to drawn and colored it in order for you to follow which I am really not ready to do and even more so as it would be in wein even if I did.
So what did you say about all "class leading" SoM's you all drool on here?
And all of them regarding amplifier classification are class H SoM's.
Thanks for the lesson!


:facepalm:
 

Stokdoof

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Been worked out for a while now. Hypex/Purifi (both have Putzeys involvement) modules seem to be leading the way currently. There are others, too. Did you take a Rip Van Winkle type nap or something? As if class A is particularly desireable....well, except in the winter maybe.
You said: ‘Did you take a Rip Van Winkle type nap or something?’

maybe you need a nap yourself, you are starting to sound a bit grumphy :)
 

antcollinet

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Andysu

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C'mon, everybody knows that class D = digital, class H = H-bridge, class G = good, class AB = absurdly better :)
solo.jpg
captain solo . and he's still frozen in class d amplification

class d is wow for THX sound system here
 
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