MOSFETs obviously drive plenty of current into very low ohm loads.Don't try to twist it again in other direction to save face. The argument here has always been, what can drive "more current" into "low impedance loads"? Mosfet or BJT output stage, for the same given amount of complementary pairs. And the answer once again is BJT commonly known as Bi-Polar. Give up your making yourself look foolish. |
“Getting back to the OP's original post. Class A circuits ( and we are specifically talking about amplifier output stages here ), just sound smoother, more homogenized, less artificial, more involving, with every attribute of recorded music reproduction, keeping one in his / her listening seat, longer. Granted, there are still audible differences, between designers and manufacturers products, but, Class A is still, imo, superior, at this particular time, in SQ. ” This is the reason I put up with the downsides of Class A amps, namely, heat, weight, and cost, cost of the amp and the cost of additional electricity. I haven’t heard any other amp topology that gets me as engaged with the music as Class A. I run a Gryphon Colosseum Stereo amp. It can generate 160w, Class A, at 8ohms, and 1250 watts at 1 ohm. It does not transition to Class B. On momentary transients, it can put out over 4000watts. The amp weighs 175lbs. I love the thing, it sings like no other amp I’ve ever owned. |
This is the reason I put up with the downsides of Class A amps, namely, heat, weight, and cost, cost of the amp and the cost of additional electricity. I haven’t heard any other amp topology that gets me as engaged with the music as Class A. Correct there’s an effortless ease to the way the music is presented with Class-A, big transients are not squeezed out at you and shot at you from the drivers, instead coming out and washing over you like a huge musical swell. Yes Gryphon!! probably the best high bias Class-A amps one can buy in the retail market today, and can do enormous current down to that 1ohm courtesy of their Bi-Polar (BJT) output stage and power supply. "Green Bias" though is another incarnation of Krells plateau (sliding) bias. Which for those who would like to know, was invented in Australia by my boss Steven Deratz in 1980 and had a provisional patent on it, but nothing came of it, and he let it lapse. I actually have always preferred the fixed (user adjustable amount) bias of the Gryphon Antillion Evo’s and my amps. I have ME amps also bjt output, some of which can also be user adjusted fixed Class-A bias. https://ibb.co/fr6SNVT https://ibb.co/D1h5nnF https://ibb.co/GcSfbCT Cheers George |
Thanks, George. The Gryphon Colosseum has three user selectable bias levels, Low, which is 30w Class A, Medium, which is 70w Class A, and High, which is 165w Class A. I can tell the difference and prefer running at High, but that’s hard to do in the summer. Still, I live in a northern city, so most of the year, I can run High without heating up my apartment too much. |
