Class A is the amplifier topology everyone respects and almost nobody gets to have because it's expensive, can be hot, and, well, most amps don't offer it.
So why do serious listeners keep coming back to it?
Because at its best, Class A is sonically untouchable in a very specific and important way.
The technical reason is crossover distortion — or rather, the complete absence of it. In Class A/B designs, positive and negative half-cycles are handled by separate output devices. At the handoff point there's a brief discontinuity that occurs thousands of times per second. Each individual event is tiny, but the cumulative effect adds a subtle texture to the sound that's most audible at low signal levels, where the crossover region occupies the largest fraction of the waveform. It's not dramatic. It's just always there, like a very faint veil you only notice once it's gone.
In Class A, the output devices conduct continuously until the handoff. No crossover. The signal passes through without interruption, and the result — particularly in the midrange and at moderate listening levels — is a purity that's genuinely difficult to achieve any other way.
We're launching the full PMG amplifier line at AXPONA in Chicago in a matter of days, and I have to say — after fifty years in this business, I'm as excited about a product launch as I've ever been. The PMG Series runs the full range from our 200 stereo amplifier, a gorgeous 200 watt amplifier with the first 20-watts pure running Class A—designed for those wisdom to know that 20 clean Class A watts in the right system embarrasses amplifiers with ten times the rated power, all the way up to what we've been calling The Beast — an 800-watt monoblock that delivers 100 watts of pure Class A before it ever thinks about crossing over. A hundred watts. Class A. From a single chassis that makes a very convincing argument for setting it on the floor next to your speakers
The specs across the line are, frankly, extraordinary. But specs aren't why I'm excited. I'm excited because we've been listening to these Darren Myer's designed amplifiers for months, and they do what great Class A has always done — they get out of the music's way and let you hear what your source and speakers actually have to say. Paired with the PMG DAC and preamplifier, and driving a pair of Aspens, the system sounds like nothing we've built before.
Class D has made extraordinary strides and I take it seriously. But for sheer midrange purity, for that almost tactile sense of natural ease — Class A remains the benchmark against which I measure everything else.
Come hear The Beast at AXPONA.
Bring your warmest expectations.
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