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The Aleph 1.2 is the third piece of Pass Labs electronics I've lived with.
I own a pair of Aleph 0 amplifiers, and I reviewed the Aleph P preamp in the February '96 Stereophile.
The Aleph 1.2 uses power MOSFETs for both of its gain stages.
These MOSFETs were chosen because they have an optimal transfer curve for use in a single-ended class-A design.
Because of my past experience with Pass gear, my expectations for the Pass Aleph 1.2 were stratospheric.
Nelson Pass's current-source design is protected by a US patent application.
Active current sources separately bias the input and output stages.
The Aleph 1.2 is unlike the original Aleph 1 in two ways.
The Aleph 1.2 has very few parts in series with the signal path.
The input signal travels through a resistor to the input MOSFET transistor, then through another resistor to the parallel output MOSFETs, with, finally, a power resistor before the loudspeaker.
Perhaps that's why I have a positive bias toward Nelson Pass's designs.