Pass Labs Amplifiers

Californian high-end amplifier maker founded in 1991 by Nelson Pass, known for heavy Class A designs and unusually open engineering.

Founded: 1991
Founder: Nelson Pass
Headquarters: Auburn, California, United States
Manufacturing: Built in Auburn, California
How to buy: Sold through specialist hi-fi dealers
Known for: Single-ended Class A, very large heatsinks, simple circuits with few gain stages

Currently, we have 2 Pass Labs amplifiers in our database. Below you can find the list with their main specs and links to their review pages.

Pass Labs Integrated Amplifier (1)
Pass Labs Stereo Power Amplifier (1)

Pass Labs Integrated Amplifier

	Model	Watts RMS (8Ω)	Amp Class	DAC	Phono
	Pass Labs INT-25	25 watts	Class A	No	No

Pass Labs Stereo Power Amplifier

	Model	Watts RMS (8Ω)	Amp Class	DAC	Phono
	Pass Labs XA25	25 watts	Class A	No	No

About Pass Labs

Nelson Pass co-founded Threshold in 1974 and started Pass Labs in 1991. The design philosophy runs against complexity: few gain stages, minimal feedback, and Class A operation with the heat that implies. Pass also runs First Watt, a deliberately tiny operation making low-power amplifiers for high-sensitivity speakers, and he publishes designs such as the Zen amplifiers for people to build at home, which almost no high-end manufacturer does.

Pass had co-founded Threshold in 1974 and is one of the few designers with a genuine public following. He publishes circuits for hobbyists to build free of charge.

Nelson Pass giving away working circuit designs to the do-it-yourself community, while selling amplifiers costing many thousands, is one of the more unusual positions in the industry and has made him something close to a folk figure among enthusiasts.

Notable models: Aleph series, XA series, INT-25, First Watt amplifiers.

Official Pass Labs website

ALL AMPLIFIER BRANDS

Links to all amplifier brands in Speaker Decision