Category Archives: Uchida / Sun Audio – Japan

all about the triode amps from Sun Audio – Japan – these amps are mostly used with 2A3 or 300B power triodes

How to rebuild a Sun Audio SV-2A3/300B Triode Amp…

Article by Carsten Bussler (2A3Manaic)

I am regularly asked whether I know who offers a used Uchida and how much it should cost. The answer to the latter question depends entirely on the condition of the amp. I always strongly advise you to include an inspection and, if necessary, a rebuild by Robert Graetke. It is not uncommon for the device to be a (amateurish) DIY device where a beginner has tried their hand at the kit…
In addition, when rebuilding the Sun Audio/Uchida 2A3, it is easily possible to provide the option of operating the 300B (by simply switching the tubes) and to retrofit the top-accessible wheels for hum balancing.

This SV-2A3, for example, is to be rebuilt at the customer’s request because the current condition of the internal structure is inadequate and the power amplifier is to be upgraded in terms of quality and sound. The power amplifier is to be given a lower overall gain so that it harmonizes better with the preamplifier. The power amplifier will be equipped with Teflon sockets for the tubes, as well as the option of conveniently adjusting the hum from the top (see above). The signal paths are wired with pure silver. Continue reading How to rebuild a Sun Audio SV-2A3/300B Triode Amp…

…a very special Sun Audio SV-2A3

It should be a very “normal” Sun Audio triode amp, which can be operated with 2A3 and also with a 300B as power triodes, as I have built it many times before. But then all came differently! Carsten Bussler had the idea that he would like to use his collection of 2A3H. At this time the power amp was already completely assembled, tuned and played perfectly. Then the new journey with the 2A3H started! It was not so easy to integrate these power triode into the Uchida. More details and pictures can be found on the blog of Carsten Bussler – 2A3 Maniac strikes back

New european distributor for Sun Audio / Uchida triode amps

The tube amplifiers of Sun Audio, Japan are now available at Acoustic Dimension in the Netherlands.

Acoustic Dimension
Mr.  Peter de Bruyn
Phone +31-15-8892700

New Mono power amps

In the product range added with a few changes. The both new monoaural amplifiers are very interesting by the strong driver stage and the interstage transformer.
New are two monaural amplifiers:

  • SV-2A3EPX (2A3 PP amplifier with interstage transformer)
  • SV-2A3TSX (2A3 PSE amplifier with interstage transformer)

Rebuilding an Sun Audio / Uchida SV-2A3 triode amp

I rebuild and build very often these Uchida / Sun Audio triode amps, so I made pictures from the rebuildung procedure. It´s published on the 2A3-Maniac blog of Carsten Bussler.

New hum balance adjustment for Sun Audio amps

We just designed a new parts for the Sun Audio amps. The parts are for the improved hum balance adjustment and brings also high quality teflon sockets for the 2A3/300B tubes. We manufacture those parts on our own maschines.