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Class A Solid State Sound

Would someone kindly describe the differences in class A sound of Pass XA.8 series, Accuphase A-70/75 series, and Gryphon class A amplifiers. Does much or any of the differences relate to mosfet (Pass and Accuphase) or bipolar (Gryphon)  output devices?  Thank you!

audiobrian
georgehifi's avatar
georgehifi
10,312 posts
 
NPN mosfets used by GamuT

N channel mosfets (not npn) can generate larger amounts of current, but it’s the "complimentary" P channel that has the problems.
To build a push/pull a/b amp that has just N channel top and bottom, the design has to be compromised to a degree, compared to when doing to same using N and P channel mosfets in class-A/B configuration.

MOSFET transistors used in industrial welding, using only one or two per rail. Eventually, GamuT sold these N-channel MOSFET amps to high-end devotees across Europe.
GamuT Di150 LE
 250Wpc into 8 ohms
400Wpc into 4 ohms
 As you can see in the Stereophile test, the Gamut even with the N channel mosfets top and bottom couldn't quite do a close to doubling act like a BJT could, and they didn't do a 2ohm test load for reasons you can only wonder about.

Cheers George
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georgehifi's avatar
georgehifi
10,312 posts
 
you’re moving the goal posts! I’m calling you on that fallacy.

Really!! Goal posts haven’t moved, still where they were, have another one.  

"To say it once again for the last time, complementary pair for complementary pair, you’ll get more amperage (current) from a BJT (bi-Polar) output stage than you will a mosfet output stage, end of story. Nothing you say can change this, give up!."
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georgehifi's avatar
georgehifi
10,312 posts
 
Your believing your own bull****!!!
 
"To say it once again for the last time, complementary pair for complementary pair, you’ll get more amperage (current) from a BJT (bi-Polar) output stage than you will a mosfet output stage, end of story. Nothing you say can change this, give up!."
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