Pass Labs

Pass Labs is a high end audio company based in Foresthill, California, USA founded by Nelson Pass, a well known figure in the high end audio community. Pass is known for unique and innovative, as well as practical, circuit designs.

Pass founded, and worked at, audio company "Threshold", where he developed the "Stasis" series of amplifiers. These designs were later licensed to Nakamichi.

The Pass labs Aleph series of amplifiers were highly regarded at the time they were introduced. These amplifiers operated pure "Class A" and contained very simple internal circuitry using MOSFETs. The Aleph amplifiers had a unique appearance, a cube with heat sinks on all four sides, a very practical solution to the high amounts of heat generated by the Class A design.

After the Aleph series of amplifiers was discontinued, a separate entity "Volksamp" was licensed to continue to produce a similar product. Aleph 30 and 60 Amplifiers were made by Volksamp until production ceased in 2003.

Currently, manufacture of the Aleph series of amplifiers is to be continued by [http://www.firstwatt.com/ First Watt] , a self described "kitchen table" amplifier company founded by Nelson Pass in 2004. First Watt initially produced power trans-conductance amplifiers (or technically a power current source). Reference: [http://www.firstwatt.com/products/f1.htm F1] , [http://www.firstwatt.com/products/f2.htm F2] These current domain amplifiers are only suitable for use with certain unique types of speakers. With respect to the Aleph amplifier line, First Watt has announced plans for the [http://www.firstwatt.com/products/alephj.htm Aleph J] , a revision of the famous Pass Labs Aleph 3/ Volksamp Aleph 30 wherein a new JFET input stage is to be added.

Today Pass Labs makes amplifiers, preamplifier and speakers. Pass Labs is also a supporter of the DIY audio community and maintains a separate internet presence for this purpose (see external links).

Current Pass Labs "X" series amplifiers use a distortion canceling balanced audio signal circuit, and continue to receive critical acclaim. See U.S. Patent number 5,376,899.

External links

* [http://www.passlabs.com Pass Labs Web Site]
* [http://www.threshold-audio.com/about.html Threshold Web Site]
* [http://www.firstwatt.com First Watt Web Site]
* [http://www.passdiy.com PassDIY] Pass DIY web site.
* [http://stereophile.com/amplificationreviews/674/ 1997 Aleph 3 Review] 1997 Review of Pass Aleph 3 in Stereophile Magazine
* [http://www.enjoythemusic.com/magazine/equipment/0701/volksamp.htm 2001 Aleph 30 Review] Review of Volksamp Aleph 30.
* [http://www.stereophile.com/amplificationreviews/1103pass/index.html 2003 XA160 Review] 2003 Review of Pass XA160 amplifier in Stereophile Magazine.
* [http://www.ultraaudio.com/equipment/passlabs_xa160.htm 2005 XA160 Review] 2005 Review of Pass Labs XA160 amplifier from Ultraaudio online magazine.
* [http://www.enjoythemusic.com/magazine/equipment/1204/firstwattf1.htm 2004 First Watt F1 Review from Enjoythemusic.com Online Magazine]
* [http://stereophile.com/artdudleylistening/105listening/ 2005 First Watt F1 "Review" From Stereophile Magazine]
* [http://www.positive-feedback.com/Issue17/firstwatt.htm 2005 Review of First Watt F1 from Positive-feedback online magazine]