advertisement


Arcam Class G amps ...

Didn't JVC pioneer a 30W super class A design about 40 years ago? Maybe this particular class G amp borrows from that JVC design but using modern devices?

You can pick up a working A-X1 and later models for very little dosh and I've often been tempted to try one.

Cheers,

DV
 
Didn't JVC pioneer a 30W super class A design about 40 years ago? Maybe this particular class G amp borrows from that JVC design but using modern devices?

You can pick up a working A-X1 and later models for very little dosh and I've often been tempted to try one.

Cheers,

DV

There's been all sorts of proprietary "non switching" circuitry designed over the years... Removing crossover distortion is only one of the benefits of class A.

It's a fascinating subject... but probably to 0.00001% of the population:rolleyes:

"Class AA", "Super Class A", "New Class A", "Servo-Drive", "Super-Feedforward", "Class XD", "Class S", "Legato Linear", "Current Dumping" and many more I'm sure.... building a better mousetrap!?
 
Didn't JVC pioneer a 30W super class A design about 40 years ago? Maybe this particular class G amp borrows from that JVC design but using modern devices?

You can pick up a working A-X1 and later models for very little dosh and I've often been tempted to try one.

Cheers,

DV
This is worth a look.
http://rover.ebay.com/rover/1/710-5...0001&campid=5338728743&icep_item=124104308736

And then of course there is.
http://rover.ebay.com/rover/1/710-5...0001&campid=5338728743&icep_item=164110834330

The A X3 bested a NAC72/135 setup in my system.
 
This site contains affiliate links for which pink fish media may be compensated.
Didn't JVC pioneer a 30W super class A design about 40 years ago? Maybe this particular class G amp borrows from that JVC design but using modern devices?

You can pick up a working A-X1 and later models for very little dosh and I've often been tempted to try one.

Cheers,

DV

!

I have an X2 and never listened to it properly... from what's being said here - best I make comparisons with the A29 'especially' as an X3 bested a NAC72/135 !
 
This site contains affiliate links for which pink fish media may be compensated.
Sorry to dig up an old thread.

Arcam do claim in advertising that the class G designs have large amounts of class A operation. The a49 for example is quoted to have up to 50w in class A.

However if you read the detail it performs "exactly like class A". But does not run in class A:

" The A49’s output stage includes a proprietary error correction circuit that modulates the modest standing currents in the
output stage and ensures a near-constant output impedance for peak currents of up to about +/- 4 amps, corresponding to well over
50W in to 8 ohms. The A49 thus behaves exactly like a classical class A amplifier up to this power level in terms of performance
but without the heat penalty."

Is this just another bit of marketing or does it add some technical advantage?
 
The SR250 is also class G apparently up to ~28 watts.. I have one its effectvely a good stereo AV amp with HDMI switching etc..
 
Isn't it closer to say that class g is a type of amplifier power supply rather than an amplifier class, as it has nothing to do with the conduction angle of the output devices?

It's just a means of supplying different voltage to the output devices to increase power efficiency.
 
It's interesting that they keep saying their class G amps run in class A for so many watts (50 for mine). Yet knowledgeable people on here (not me!) think it is not class A for any where near that as they don't get hot/not enough heat sinking etc.
 
The definition of a class A amp is that the output devices each conduct a full 360 degrees of the input. It has nothing to do with how the power rails are supplied or switched to a higher/lower voltage to track the input level.

For their class g example in that pdf to operate in class A only one of the output devices would be conducting, until they switched in the other output device and moved to class a/b operation.

They could well be doing both, but from the marketing there's claims of class A like operation and sonic properties and no comment of running the full 360 through each output device.

That strongly suggests high bias class a/b with multiple rail voltages, not class A. Could be wrong though
 
I have the A49, currently twiddling its thumbs operating purely as a pre into my active ATC’s. As an integrated, it surprised (shocked!) a good few people who thought they knew “the Arcam sound”. It’s powerful, crisp yet smooth, and fabulously featured including balanced in/out and dual speaker connectivity.

In terms of class, I can only say it sounds ClassY.

Here all week folks; check out the buffet.
 


advertisement


Back
Top