First Watt Aleph J

The Aleph J carries on in the tradition of the Pass Labs Aleph series, combining those elements that were particularly right about the Aleph 3 and 30, and re-thinking those areas open to improvement. Unlike its First Watt predecessors the F1 and F2, the Aleph J is a voltage source amplifier – a regular sort of amplifier like the ones you already know and love.

There are differences between the Aleph J and its predecessors:

1) Improved power supply filtration with about 20 dB less voltage ripple

2) Reduced gain on the active current source, giving better overall performance into 8-16 ohm loads

3) Input stage using high quality matched JFETs

4) Much higher input impedance and vanishing capacitance

5) 15 dB less negative feedback.

6) Even greater stability, operating without lag compensation

7) 15 dB less noise

8) No electrolytic capacitor in the signal path

Some things have remained the same – the Aleph J has the same basic 2-stage topology and uses output MOSFETs operating in single-ended Class A mode. It’s distortion character is still 2nd harmonic, and it’s sound is still natural and liquid. It is still very reliable. I don’t know of a load that can damage it.