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β22 Stereo Amplifier / Linestage Preamp/ HeadPhone Amp

This sale is withdrawn.

A completed set of Beta22 amplifier and Sigma22 PSU that can be configured as a linestage preamp, a headphone amp and even a low power amp to drive sensitive speakers.
This amp is built as a 2 amps for stereo channels + 1 amp as active ground.

More information here:

It is built on a backplane board :
Hence the amp looks neat and sleek, will less wirings running all over the place.

Powering the amp is the Sigma22 regulated PSU:

Transistors, including the matched quad of 2SK170/2SJ74 per channel were bought from AMB LAB during those years when they were available at their online shop. Hence you can be assured that they are genuine. So there are a total of 3 matched quads of these precious FET in this amp.

This projected was built and tested, played without a chassis some time ago. I had the ambition of building a customised superb heavy steel chassis which did not materialise due to many distractions. Despite that it was commissioned to work, i do suggest that you read the information at AMB LAB, power up, test and monitor and trim the dc offset carefully.

A lot of effort and time has gone into putting this together using premium parts from legit /authorised sources.

I am asking for 380USD + shipping.
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Some pics


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