Interesting AU-D33 article

[JimEGR]

Great to see some modern media covering "vintage" Sansui. Not a lot out there on this AU series. Maybe considered the beginning of the decline. Still an interesting part of Sansui history, and low THD Super Feedforward. -

https://www.hifinews.com/content/sansui-au-d33-integrated-amplifier

 

[Hyperion]

That was interesting - thanks for posting

 

[Leestereo]

...Not a lot of out there on this AU series. Maybe considered the beginning of the decline...

The early 80s saw a dramatic increase in the valuation of the yen vs other currencies and this consequently resulted in Japanese products being more costly in export markets. In order to maintain their competitive pricing model, there was a need to lower manufacturing costs; this is evident in the lower Sansui models of that time. For example, in the AU-D33, one notes the use of an op amp in the phono stage instead of discrete transistors, and TO-3P transistors instead of all metal TO-3s in the output stage. IMO, there isn't a performance penalty in the aforementioned changes; the NJM2043 op amp used is a quite good one and the TO-3P transistors can perform as well as the TO-3 types. Where there was a step back in performance was in the power supply; the output current capacity is reduced and this can be observed as a lower power output capability with loads lower than 8 ohm. For example, whereas the Sansui brochure for the AU-D33 only lists 50wpc into 8 ohms, the one for the AU-317 lists 50wpc into 8 ohms and 72wpc into 4 ohms.


Graph from https://www.hifinews.com/content/sansui-au-d33-integrated-amplifier-lab-report