Introduction
The Aleph 0 is a single ended Class A audio power amplifier, the first product produced by
Pass Laboratories. It combines completely new design thought applied to a traditional
topology and the experience of twenty five years of amplifier design.
This power amplifier flows from a commitment to create the best sounding product: a simple
circuit with the most natural characteristic. The Aleph 0 integrates power Mosfet devices and
single ended Class A operation in a simple topology in order to deliver natural sound, the
reference for naturalness being taken as the acoustic characteristic of air.
Consuming four times the rated output power, single ended Class A makes ordinary push-pull
circuits appear comparatively efficient. This inefficiency has been a deterrent to designers,
limiting this "king" of Class A circuits to preamps and input stages.
I feel that in specialized and demanding applications, the energy penalty is worth the purity of
performance obtainable from single ended Class A operation. This purity delivers the most
musicality and listening satisfaction per watt of any operating mode.
Over the years I have remained fascinated by the characteristic sound of the single ended
topology, but until now I did not have the opportunity to bring such a product to market.
A very few people are involved in the production of this product. I supervise all phases of the
construction, and I test and listen to each amplifier myself. If you have questions, comments,
or problems, please feel free to contact me directly.
Thank you for purchasing this amplifier. It is my sincere hope that you will enjoy its sound as
much as I do.
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Nelson Pass
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Date:
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