Matt's Sansui AU-317rebuild

finally some pictures

Here are a few quick shots of the AU-317. I'm listening to it as I type and it sounds wonderful - thank you guys for all the help!

I still have some bleedthrough from aux to tuner but not from tuner to aux. That may be normal, but if I'm listening to the tuner and the aux source is still connected I can it hear on quiet passages. This may just be due to wire dressing as well .. I'll pop the cover again at some point and check that.

The TU-317 is from AKer howardtheduc (great deal!) and it is also awesome. He posted the TU-317 on BT a few days after I acquired AU-317. It was meant to be!

-Matt

Fine looking pair in great condition and both with rack handles too! - Would be proud to own them - Next time you pop the hood, please post some pix of the internals - Happy listening

Hi Matt,

Re the bleed through, have you tried swapping the tuner and the aux source inputs and rechecked the bleed through?

Cheers

John

Hi John,

Yes, I have swapped the tuner and aux sources and the bleed is always from aux to tuner, regardless of what the actual source is (tuner or PC).

AUD101 - I will post some internal shots as well at some point. I plan to replace the trimmers the next time I have to place an order. The trimmers I purchased have the adjustment screw on the side as opposed to the top (shame on me for not reading the spec sheet closely enough).

-Matt

Hi John -

Regarding the bleed through, it looks like my source may be the culprit. The tuner does not bleed when connected to either aux or tuner inputs. However, my laptop bleeds on both aux and tuner inputs, even when the volume on the laptop is turned way down. So I don't think this is a real issue. I'm going to chalk it up to either my laptop or the cable I'm using to connect the laptop to the AU-317.

-Matt

Well I'm not out of the woods yet with this amp. I just hauled a turntable up to test the phono input and it turns out that the right channel phono is dead. That's the channel I had put the wrong transistor into, so I suspect that has something to do with it. Unfortunately I used all of the KSA992s I had, so I'll have to wait and place a Mouser order. I'll get the trimpots at the same time. I'm hoping that replacing the three KSA992s on the right channel will be enough to fix it.

-Matt

I received a large Mouser order today that included parts for my next project (an AU-717) as well as the trimmers and KSA992s for the AU-317. After close investigation I found two cracked KSA992s on the right channel - I swapped these out and now everything is perfect!

I also installed the bias trimmers and set the bias voltage. What a difference the new trimmers make. Voltage is steady and very easy to adjust down to 1/10th of a mV.

The offset trimmers are next. I'll be sure to take some good interior shots tomorrow before buttoning it all back up.

-Matt

inside shots

Here are a few interior pictures of the finished product. The first picture shows the fully rebuilt amp. The second picture is a close up showing the new trimmers, which made a huge difference in ease of adjustment. The third picture shows the 1uF / 100V caps I installed across the new main filters. You can also see the one solder pad that didn't make it - fortunately it is on one of the unused legs of the main cap.

All in all, this was a fun and rewarding project that came out very well, especially considering the condition of the amp when I received it. Thanks for all of the advice and help during the rebuild!

-Matt

PS - I'm now working on an AU-717 that was purchased here in BT. The 717 is a real beast, and I'm excited to compare it to the 317 when its done.

Excellent work Matt - :thmbsp: - Another Sansui AU-317 refurbished to play on for many years more to come!

Yep, well done Matt :thmbsp:

Bravo Bravo… encore BRAVO!

Great job! Going to check with my cousin to see if he wants it. We have't found one yet so this will be a good unit for him.