Nelson Pass - Pass Laboratories (+ News & Reviews) - At Musicraft (Derby)

[Musicraft (Derby)]

Musicraft (Derby) is pleased to announce that we now also support Pass Laboratories.



Pass Laboratories, Inc. was founded in 1991 by Nelson Pass. Operating out of his shop at home, Pass developed prototypes of a single-ended Class A amplifier design. At the same time, he and Mike Burley were constructing an in-house machine shop with three home-built CNC milling machines with which to produce the amplifiers when the design was finished.



The first product, the Aleph 0, shipped in 1992. It was a mono-block design rated at 70 watts into 8 ohms, and was unique in using three gain stages of power Mosfets including a push-pull output stage biased by a big constant current source. The amplifier operated as single-ended Class A up to its 70 watt rating and in push pull Class A at higher wattage.



At this time, Nelson hired his next-door neighbour, Elena Tong, to help with producing the amplifiers, and she manages much of the company to this day. A stereo version called the Aleph 0s followed after, along with a preamp called the Aleph P. A larger version of the Aleph 0 called the Aleph 1 shipped the following year, and was a mono-block rated at 150 watts.



https://www.passlabs.com/


Pass Laboratories. 20 Years and Counting.


Website: http://www.musicraft.co.uk

Please call 01332 346284, 07727 272443 or email info@musicraft.co.uk

Hours of business are Monday to Saturday 9am-8pm, Sunday 10.30am-4.30pm (please call before travelling)


***** https://www.facebook.com/MusicraftUK *****


***** Musicraft website - Special Offers list http://www.musicraft.co.uk/special-offers/ *****


Thanks

Rick @ Musicraft

[Musicraft (Derby)]

Pass Laboratories NEW DESIGNS -



In 1994 Pass Labs released a newer Aleph design which simplified the circuit from three gain stages down to only two stages and used a newly patented power current source to bias the single-ended output stage. The new circuitry was incorporated into a revision of the Aleph 1, the 200 watt Aleph 1.2, and smaller models, the 100 watt Aleph 2.

In 1994 Nelson was joined by Wayne Colburn, who began working on improved version of the preamp and on a new phono stage. The company received two patents this year, one of them the design that became the SuperSymmetric circuit in use today.

The amplifier was highly acclaimed, and was called the “Amplifier of the Decade” in Stereophile magazine.



In 1995, the 30 watt Aleph 3 and Aleph L preamp were released. Also in 1995 the Joseph Sammut left his position at Krell and became operations chief at Pass Labs. The following year he was followed by designer Desmond Harrington.



In 1997 Wayne Colburn’s efforts bore fruit in the revised Aleph P, the Aleph Ono phono stage, and the D1 digital to analogue converter.




Pass Laboratories. 20 Years and Counting.


Website: http://www.musicraft.co.uk

Please call 01332 346284, 07727 272443 or email info@musicraft.co.uk

Hours of business are Monday to Saturday 9am-8pm, Sunday 10.30am-4.30pm (please call before travelling)



***** https://www.facebook.com/MusicraftUK *****


***** Musicraft website - Special Offers list http://www.musicraft.co.uk/special-offers/ *****


Thanks

Rick @ Musicraft

[Musicraft (Derby)]

Pass Laboratories NEW LOCATION -



By 1995 the company had outgrown Nelson's buildings, and building was begun in a new location. In 1997 Pass Labs moved out of [/b]Nelson’s[/b] shop space and into a new facility in Foresthill. By then, even more space was needed, and was leased for storage elsewhere. Nelson’s original shop continues to house research.

In 1998 the company released the X1000, the first amplifier using the patented SuperSymmetric topology. The X1000 achieved 1000 watts with high performance, local feedback and only two gain stages: a cascoded differential pair of transistors and a large bank of complementary output followers. This ground breaking design has formed the amplifier products from Pass Labs to the present day.



The X1000 also introduced Desmond Harrington’s signature mechanical design work. The X1000 was followed by the mono-block X600, the stereo X350, and the stereo X250 and X150 models.



In 1998 and 1999, Wayne’s preamplifiers X0, X1, and Xono were released, and Joe Sammut became the President of Pass Labs, freeing Nelson to devote all his time to product.




Pass Laboratories. Elevating your audio experience.


Website: http://www.musicraft.co.uk

Please call 01332 346284, 07727 272443 or email info@musicraft.co.uk

Hours of business are Monday to Saturday 9am-8pm, Sunday 10.30am-4.30pm (please call before travelling)



***** https://www.facebook.com/MusicraftUK *****


***** Musicraft website - Special Offers list http://www.musicraft.co.uk/special-offers/ *****


Thanks

Rick @ Musicraft

[Musicraft (Derby)]

Pass Laboratories MORE IMPROVEMENTS -



In 2002 the first XA amplifiers were released, combining the X and Aleph topologies into balanced single-ended Class A amplifiers with many of the characteristics of both the X and Aleph series. The XA200 was rated at 200 watts mono, the XA160 was 160 watts.

In 2003 the company produced the X150.5, the first major improvement of the X150 amplifier, and followed it with “.5” revisions to the other X amplifiers through 2003 and 2005.



In 2007 Pass Labs is applying the “.5” advances to the XA series of amplifiers, with the XA100.5, XA60.6, and XA30.5 shipping as of this writing. These revisions dramatically lower distortion and noise and also dramatically improved the performance of the amplifiers into low impedance loads.



Also in 2007, Desmond Harrington assumed responsibility as President of the company. Nelson and Wayne continue development work, Joe manages sales and marketing, and Elena and Kent English manage the rest of the company. All these people still like each other, and sit in the same office everyday. This way they can all can hear everything that’s going on, laughing about most of it.




Pass Laboratories. Elevating your audio experience.


Website: http://www.musicraft.co.uk

Please call 01332 346284, 07727 272443 or email info@musicraft.co.uk

Hours of business are Monday to Saturday 9am-8pm, Sunday 10.30am-4.30pm (please call before travelling)



***** https://www.facebook.com/MusicraftUK *****


***** Musicraft website - Special Offers list http://www.musicraft.co.uk/special-offers/ *****


Thanks

Rick @ Musicraft

[Musicraft (Derby)]

Pass Laboratories INT-25 Class A Integrated Amplifier -



At Pass Labs we build FET amplifiers with excessive output stages, huge heat sinks and massive power supplies. We use the highest quality components in simple linear topologies, assembled and tested with care and subtlety. They measure well, sound great, and are reliable. Twenty plus years of ongoing innovation have kept the X and XA amplifiers at the forefront of high-end audio.

The INT-25 embodies all this and less. A smaller stereo Class A amplifier at a lower price, it takes advantage of the lower power requirements to have simpler single-ended circuitry and fewer parts in the signal path. This also allows elimination of degeneration, “that other negative feedback” in all stages.

Simpler and fewer gain stages improves speed and stability. Lower voltages means the ability to run gain devices at higher bias currents, more deeply into Class A. Newer power FET technology replaces banks of parallel small transistors with a single pair of industrial devices, each having a 700 watt/40 amp rating. With no current-hogging issues and a new constant-current bias circuit to compensate for temperature drift, they connect directly to the loudspeaker without ballast resistors for lowest possible distortion and highest damping factor. No degeneration also increases the efficiency and Class A operating current, allowing greater Class A operation into low impedance and reactive loads.



The simple front end circuit uses two pairs of our favourite NOS complementary FET's in common-source mode in a current feedback (CFA) configuration.

The preamp section is a simplified single-ended version of the one used in the INT-60 and INT-250 with three line level inputs and no line level output.

Everything done in the signal chain from the microphone to the loudspeaker, forever leaves an indelible mark on the music. The XA25 amplifier section is direct coupled requiring no DC servos or frequency compensation, neither adding too or subtracting from the experience.

As with all Pass amplifiers, the technology and construction are strictly in the service of the listening experience. The INT-25 measures superbly, but its subjective qualities are most special. In an industry where products with great specs are often found to be dry and boring, this amplifier breathes new life into the music.



Pass Laboratories INT-25 Class A Integrated Amplifier UK RRP £7190


Pass Laboratories. Elevating your audio experience.


Website: http://www.musicraft.co.uk

Please call 01332 346284, 07727 272443 or email info@musicraft.co.uk

Hours of business are Monday to Saturday 9am-8pm, Sunday 10.30am-4.30pm (please call before travelling)


***** https://www.facebook.com/MusicraftUK *****


***** Musicraft website - Special Offers list http://www.musicraft.co.uk/special-offers/ *****


Thanks

Rick @ Musicraft

[Musicraft (Derby)]

Stereophile magazine reviews Pass Laboratories INT-25 Class A Integrated Amplifier -

"Every day, the Pass Labs INT-25 sounded like a purer, more austere instrument than the combination of the Pass Labs XA25 amplifier with any of my in-house preamps. Every day, I noticed how the INT-25 offered a less obstructed and more transparent view of what my source components were excavating from my recordings. In addition, it made my hi-fi less hi-fi and the musicians more there—with a lower level of editorializing than I've gotten from any previous amp-preamp combination I've reviewed. My new solid-state reference."

https://www.stereophile.com/content/...ated-amplifier



At Pass Labs we build FET amplifiers with excessive output stages, huge heat sinks and massive power supplies. We use the highest quality components in simple linear topologies, assembled and tested with care and subtlety. They measure well, sound great, and are reliable. Twenty plus years of ongoing innovation have kept the X and XA amplifiers at the forefront of high-end audio.

The INT-25 embodies all this and less. A smaller stereo Class A amplifier at a lower price, it takes advantage of the lower power requirements to have simpler single-ended circuitry and fewer parts in the signal path. This also allows elimination of degeneration, “that other negative feedback” in all stages.

Simpler and fewer gain stages improves speed and stability. Lower voltages means the ability to run gain devices at higher bias currents, more deeply into Class A. Newer power FET technology replaces banks of parallel small transistors with a single pair of industrial devices, each having a 700 watt/40 amp rating. With no current-hogging issues and a new constant-current bias circuit to compensate for temperature drift, they connect directly to the loudspeaker without ballast resistors for lowest possible distortion and highest damping factor. No degeneration also increases the efficiency and Class A operating current, allowing greater Class A operation into low impedance and reactive loads.



The simple front end circuit uses two pairs of our favourite NOS complementary FET's in common-source mode in a current feedback (CFA) configuration.

The preamp section is a simplified single-ended version of the one used in the INT-60 and INT-250 with three line level inputs and no line level output.

Everything done in the signal chain from the microphone to the loudspeaker, forever leaves an indelible mark on the music. The XA25 amplifier section is direct coupled requiring no DC servos or frequency compensation, neither adding too or subtracting from the experience.

As with all Pass amplifiers, the technology and construction are strictly in the service of the listening experience. The INT-25 measures superbly, but its subjective qualities are most special. In an industry where products with great specs are often found to be dry and boring, this amplifier breathes new life into the music.



Pass Laboratories INT-25 Class A Integrated Amplifier UK RRP £7190


Pass Laboratories. Elevating your audio experience.


Website: http://www.musicraft.co.uk

Please call 01332 346284, 07727 272443 or email info@musicraft.co.uk

Hours of business are Monday to Saturday 9am-8pm, Sunday 10.30am-4.30pm (please call before travelling)



***** https://www.facebook.com/MusicraftUK *****


***** Musicraft website - Special Offers list http://www.musicraft.co.uk/special-offers/ *****


Thanks

Rick @ Musicraft