Projects

AU20000:

One of the largest amps Sansui has ever built, one of the most beautiful, both to look at and to listen to. All electrolytics replaced, all small transistors replaced, solved the preamp power supply board problem once and for all in the best possible way. LED illumination for the meters, taken apart and cleaned the rotary switches for the tone control, the mute and other switches. Placed a new bi-color LED for on/off/protection indication, fitted new 3-wire mains cable. A true no-compromise AU20000.

AU919:

Complete overhaul, all electrolytics replaced, including the ‘big four’ which originally contain two capacitors, so in each I put two new Kemet/Rifa 15000 uF 63 Volt in. Of course all the notorious ‘black-flag’ capacitors are replaced, as well as the triple diodes in the power amp and the MD phono preamp. This replacing of the triple diodes is not stricktly necessary but I replaced them with LED’s which just looks nice…

Only recently I compared the AU20000 with the AU919 and although both sound stunningly good, I found the 919 to be more refined and having a better stereo imaging, I suppose this is largely due to the far superior power supply of the 919, but als of course to the presence of the DD/DC circuit.

PA100:

Not exactly ‘hifi’, not even stereo, but still a true Sansui, by sound, by buildquality, by everything. A rarity in my country, because in the late 1960-ies, a Sansui would not have been the logical choice for a 100 Volt PA amplifier to drive a few dozen ceiling mount speakers in a small supermarket.

The owner of this one asked me to convert Mic 1 and Mic 2 inputs to not only accept a balanced microphone signal, but also to have phantom power for condensor microphones. I fitted two new 2:1 audio transformers to replace the original 1:10 ones and agreed to sacrifice the RCA connector for the phono input on the back panel to fit the on-off switch for the phantom power. The line amp turned out to produce a lot of noise, so I had no choice but to replace all the small transistors and some of the composite carbon resistors, mainly on the input side, where they contribute most to the noise. The power amp has two transformers in the signal path, one interstage transformer to drive the two power transistors, and an output transformer, to allow for various output impedances, from 4 Ohms to 125 Ohms, to drive 100 Volt speakers. I chose not to replace any of the original lightbulbs, since they were all working fine. Once they start to fail, they will be replaced by LED. For now, I kept as much of the original amp as possible.

AU/TU3900:

Only small electrolytics replaced, all small transistors with the corroded wires replaced, new LED for on/off indication placed, new speaker terminals for speakers A. However good they may be, I refuse to install gold plated terminals because I think it looks tacky on an old amp like this…

Soundwise I like the AU3900 and in general this series for its ‘sweetness’ for which Sansui is well known.

Model 210 receiver.

All electrolytics replaced, stereo decoder repaired, amplifier modified with bias control (originally not present!) and installed LED scale, meter and indicator needle illumination. Meticulously cleaned inside and out by a good friend of mine. Modest power, only 2 x 12 Watts at 8 Ohms but with original Sanken power transistors a true joy to listen to with a sensitive pair of speakers.

AU317:

Perhaps one of the most versatile amplifiers that Sansui has ever built; compact in size, powerful enough to drive most speakers, originally equipped with the beautiful Sanken power transistors, but they are easy to replace with newer model Sanken transistors if necessary. Easy to modify and service. I have four of these, two of them are for sale. Contact me for details.