You Can Have My Class AB When You Pry It From My Cold Dead Fingers

[twiiii]

The Class D amps I have heard don't come close to Class A amps and Quad balanced amps. Sure they are cheaper and those that are not are just ripping off the consumer. Remember there is a succor born every minute. As always the final result has more to do with the the final execution rather than the theory.

 

[E-Stat]

They look all lost and alone on the old-school shelving.

I call that RFI isolation as switchers can light up radios in close proximity!

And they remain out of sight in the utility closet to the right of the New Advent.

 

[Archguy]

OKAY WHAT'S THE CONVERTIBLE...

 

[E-Stat]

Honda S2000.

 

[Archguy]

Sweet. One of the best sports cars out there

 

[Archguy]

Sorry Mr OP, I've turned yet another audio thread into a car thread.

As you were, gents

 

[Pio1980]

I wish someone would tell me what class the Luxman M-200 is.
That damned amp keeps harassing my consciousness.

http://audiokarma.org/forums/index.php?threads/luxman-m-200-amplifier.820403/

This guy says it "runs warm"...
http://thetannhausergate.com/index.php/2016/06/30/luxman-m-200-class-a-stereo-power-amplifier/

My swag re class 'A' is "no".
http://www.luxman.com/product/detail.php?id=24

 

[Cadillac Kid]

I'm sure the flippers will be happy to slide the Class AB amp from your warm, over-heated, little fingers.

 

[Hak Foo]

What surprised me was that they haven't been able to hit some basic marketing-friendly specs on class D kit. Yeah, it's the size of a matchbook and rated 300 wpc, but at what distortion level?

I see the small PCB amplifiers quoted output at 0.1 or even 1% THD ratings, when even modestly priced class AB kit by the late 70s/early 80s, were pushing .02% or less.

I was looking at a video where someone rebuilt an early-80s STK-based reciever with a couple of the modules, which looked sort of fun as a project, but I'd suspect he actually produced a product with lesser performance than what it left the factory with.

 

[mjw21a]

Dunno what this is, but it looks a lot like class 'D'.

http://davidberning.com/products/zh230

http://davidberning.com/reviews

Damn, if it cost a quarter of that I'd be queueing for one right now to replace my current tube amp. Looks fantastic.

Maybe the Chinese will copy it in ten years or so. Unless Trump wins his trade war that is

 

[DaveVoorhis]

Tubes are used in class A and AB output designs because when they clip, they tend to produce more even harmonics than equivalent clipping when using semiconductors. This may sound better than semiconductors under the same circumstances.

That is not the case. The determining factor is fundamentally circuit topology.

That's undoubtedly at least partly the case, but there do appear to be some fundamental differences in distortion harmonic content between tubes and transistors even when controlling for circuit topology. E.g., see https://spectrum.ieee.org/consumer-electronics/audiovideo/the-cool-sound-of-tubes/3 and particularly https://spectrum.ieee.org/consumer-electronics/audiovideo/the-cool-sound-of-tubes/3/distortion

 

[mhardy6647]

I wish someone would tell me what class the Luxman M-200 is.
That damned amp keeps harassing my consciousness.

http://audiokarma.org/forums/index.php?threads/luxman-m-200-amplifier.820403/

This guy says it "runs warm"...
http://thetannhausergate.com/index.php/2016/06/30/luxman-m-200-class-a-stereo-power-amplifier/

The guts look pretty generic; at 25 wpc and given the form factor, I'm guessing AB. Might be biased "hot", though.

Interesting that Luxman cagily shows no power consumption in the back apron cheesecake photo

 

[Pio1980]

What surprised me was that they haven't been able to hit some basic marketing-friendly specs on class D kit. Yeah, it's the size of a matchbook and rated 300 wpc, but at what distortion level?

I see the small PCB amplifiers quoted output at 0.1 or even 1% THD ratings, when even modestly priced class AB kit by the late 70s/early 80s, were pushing .02% or less.

I was looking at a video where someone rebuilt an early-80s STK-based reciever with a couple of the modules, which looked sort of fun as a project, but I'd suspect he actually produced a product with lesser performance than what it left the factory with.

They are listed non FTC. The TDA311# chips actually do ca 30-35 WPC@8 Ohms with a full capacity ps.
The Dyna Stereo 70 should have been adverted as a Stereo 60 in all honesty as sold under FTC rules.

 

[Tom Bombadil]

I've experimented with the garage system and enjoy a Bruno Putzeys designed Ncore amp using OEM modules and basic cosmetics. With balanced outputs, it ran about $800.

Nice. $800 for an Ncore amp is a good price.

 

[Pio1980]

Certain amps seem to have a better dynamics contrast than others, class 'A', class 'D', simpler class 'AB'. Solid state class AB in general seem to lack in dymamic contrast, power notwithstanding. Some simply get one closer to the realism of the event

 

[JoeESP9]

Dunno what this is, but it looks a lot like class 'D'.

http://davidberning.com/products/zh230

http://davidberning.com/reviews

Unless Mr Berning has produced another invention beyond his OTL circuit the amplifier in question is an OTL amplifier. OTL has nothing whatsoever to do with Class D. In any case, tubes are not suited for Class D operation. With Class D amplifiers the outputs operate as very fast switches. Tubes can't switch on and off fast enough.

FWIW: Every OTL amplifier I've ever heard has produced superb sound. I use an OTL amplifier (Little Dot MKII) to drive my headphones. If I could afford it I'd use one of his more powerful amplifiers to drive my Maggies or Acoustats. Those who have them apparently hold onto them as I rarely see any on the used market.

Transcendent Sound also makes a relatively powerful OTL amplifier. It's another amp I covet along with a Berning. Banks of output tubes make OTL's pretty good space heaters.

 

[Pio1980]

There's no reason an otl tube amp can't be designed as switchmode. I do not know exactly how the newer Berning amps operate, but he has something novel and proprietary going on.
http://davidberning.com/products/qz

 

[JoeESP9]

There's no reason an otl tube amp can't be designed as switchmode. I do not know exactly how the newer Berning amps operate, but he has something novel and proprietary going on.

Admittedly it's a new application of tube technology. However, it's still not Class D. If you know of anyone who has managed to make tubes switch on and off fast enough for Class D operation I'd like to know who they are.

 

[Frank Sol]

I'm more into compact units these days... my age is probably the reason

So... the small D amps work well for me. They compete with AB/A amps in their wattage range - IMO

Example: Decent tube pre with a D amp (with good power supply) going into high efficient speakers

 

[E-Stat]

Nice. $800 for an Ncore amp is a good price.

You may be aware that the Bel Canto products like the "Black Series" are Ncore based.