What makes the Sansui AU-717 integrated amplifier so special?

The Sansui AU-717 integrated amplifier is one of those pieces that I just love working on. Sansui designed and built the AU-717 at a time when labour was cheaper. The money went into build quality, parts and layout and this resulted in a timeless, enduring design that is appreciating in value.

What are the things I like about the AU-717?

Theres quite a few thing I like about the AU-717. The layout is very clean, they used proper shielding over all AF sections that we like to see, the shielding itself is attractive ,matching the clean black gloss finish elsewhere. The PCB locations and mounting make for some fairly quick work, especially when pulling the driver sections.

What kind of Fet does the au717 use?

The Au717 uses an interesting 1st stage topography along with a field-effect transistor FET (2SK97) differential package, and quasi complimentary pairs at TR01/02 & Tr03/04. It is recommend to update the TR01/02 and Tr03/04 as was performed in this unit with ZTX694B and 992’s BJT’s.

Do you need to replace varistor in au717?

One important thing to note is the AU717 used quite a few VD1212 type varistor diodes. These should all be removed and replaced with something a little more reliable and new, two 1N4148 in series (cathode to anode) work excellent. Also, note we have 4X 82.5 ohm fuse-ables that need to be replaced with MOX or equivalents.

Why is my Sansui AU-717 amplifier not working?

Corrosive glue and leaking capacitors mean this PSU/protection board needs major repair. The speaker protection relay was playing up in this particular AU-717. Out with the old, on the right, in with the new, on the left. The replacement relay has extra terminals, but these are not needed and don’t affect operation.

Is it OK to repair an old Sansui stereo?

It’s a shame, because repairing an old piece of Stereo gear without doing a recap/restore just means that more problems will appear soon. In addition to the repair, many parts should be replaced. All these old Sansuis are almost 40 years old or more now.

What kind of tonearm does Sansui AU-717 use?

The AU-717’s moving-magnet phonostage proves equally enticing, using our restored Thorens TD-125, courtesy of Vinyl Nirvana, with an SME 3009 tonearm and Ortofon VMS 20 mk. II cartridge.

How many Watts Does a Sansui audio amplifier produce?

The 85-watt-per-channel Sansui amplifier is rated conservatively, and reviews from Stereo Review and Audio from when the AU-717 was new indicate that it produced around 100 watts into an 8-ohm load; more than enough to drive all but Magnepans to a major level.