But skrivis, do you feel there is something about the sound of Pass equipment that is not ideal?
Well, I've listened to Threshold and Pass Labs stuff a few times, and it never seemed really _bad_, but it never seemed to be that great either. It definitely didn't seem to be a good value for money.
I think that whole business of 15 bazillion output devices, amplifier/arc welder was rather wacky. Pass was right in there with ML, Krell, and Rowland. I also think Pass's Zen stuff is wacky too. And then there's El Pipe-o.
Frank's approach, in the main, seems to be to take a relatively simple, well-proven and well worked-out circuit and make it perform as well as possible. Some of the other designers get overly complex. I feel that AVA equipment performs as well or better than anything else on the market, is less expensive than a lot of other equipment, and it's very robust. (Partly because it's less complex so there's less to break.)
Frank's use of MOSFETs might be a good example. Transistors are more linear than MOSFETs. But, in order to use transistors, you need to add a whole lot of circuitry to keep them from destroying themselves. Then you add more circuitry to keep the protection circuits from producing audible effects. You finally wind up with wildly expensive equipment, and I don't see that you get better performance.
It seems to me that it's better to choose MOSFETs and get them working within their linear area of operation. Good MOSFET amps sound, to me, as good or better than anything else around, and they're a lot simpler. The designer can spend their time making a few things right, rather than spreading themselves out making a whole batch of things right (and maybe not having enough time to do a great job).
Another example: Hmmm... then we want to eliminate coupling caps, so we'll add a bunch of stuff to keep DC from appearing at the output and destroying your speakers. So we add lots of complexity to do what a simple capacitor does perfectly well.
Nelson Pass is obviously a very talented engineer (probably at or near the genius level), but I think he enjoys engineering too much.
He gets a neat idea for a new circuit or topology and runs with it. It's really cool, and he comes up with really cool stuff. But I'm not sure it's objectively better, although it is really cool.
I wouldn't tell anyone to absolutely not buy Pass gear, but I'd say that you can do much better for your money with AVA.
Does that explain it?
