Aleph 3

About the Aleph 3

The Pass Labs Aleph 3 is a stereo power amplifier featuring a single-ended, Class A output stage with a power output of 30 watts per channel into 8 ohms. It uses just two gain stages, unlike conventional amplifiers with multiple stages, resulting in a very direct signal path and enhanced purity of sound. The amplifier operates in pure single-ended mode over its entire operating region without a pull stage, clipping occurs when output MOSFETs reach cutoff. It has a current source output stage topology optimized for real loudspeaker loads, improving performance across impedance and reactance variations. The Aleph 3 requires no bias or offset adjustments, with operating parameters defined by physical constants for long-term stability. It delivers detailed, spacious, and natural sound with primarily second-harmonic distortion, which is less offensive to the ear. The amplifier is known for its smooth, tube-like sound quality, comparable to high-end single-ended tube amplifiers, and is fully biased Class A, generating significant heat requiring good ventilation. Dimensions are 12" W x 6" H x 12" D, weighing 38 lbs. It consumes about 250 watts continuously and has a damping factor of 100. The Aleph 3 was introduced in 1996 and remains a revered design for audiophiles seeking natural and authoritative sound reproduction.