CLASS A AMPLIFIERS

Chuck, thanks. It's interesting that Pass suggests that "These are not design oversights or flaws in the XA-200, but rather a condition of the very highly biased Class A operation." I don't recall this "reasoning" from some other Class A amplifier manufacturers. It may even contradict what is commonly percieved as techincally available from Pass' previous designs.

Onemug, Jon recently told me the same thing re: a different Class A/AB Threshold amp.

highly biased Class A operation

This is probably Mr Pass' way of saying the device is operating in "deep class A". Just the PS is well over the expected 4x the energy output rating fro class A.

I think I read somewhere that this is acharacteristic of pure class A amps in general and that it also applies to tube amps. If I remember correctly, and I am getting old, I believe CJ told me that it was a characteristic of my premier 11a, but I am not sure. The topic came up with CJ when I was asking them questions concerning tube amps and driving thiel speakers. I maybe speaking to much to generalities and not enough to specific circuit topologies.

Chuck

Czbbcl , that is not a characteristic of class A amps although this may be a limitation of Pass designs. As stated above Gryphon class A amps double output from 150W @ 8ohms all the way to 2400W @ 1/2 ohm (5000W peak). In the real world your home electrical circuit will be the limiting factor with well built true class A designs with HUGE power supplies. - Jim