I have a Sansui AU-717 integrated that I bought new with paper route money in the mid-70’s (I’m 63 now). It’s in excellent condition and I still have the owners manual…wish I’d saved the box. The amp works perfectly but I suspect is overdue for caps/bias adjustment, cleaning, etc. The cover has never been off.
I do not have the knowledge or skill to attempt it myself. Looking for quality service recommendations ideally in the Atlanta area. I prefer not to ship it if possible. Appreciate any guidance.
-Mike (first post on DIY)
I do not have the knowledge or skill to attempt it myself. Looking for quality service recommendations ideally in the Atlanta area. I prefer not to ship it if possible. Appreciate any guidance.
-Mike (first post on DIY)
Thanks @lexxtox. I reviewed the thread but not sure if perhaps I missed something. Looks like a few chaps talking about growing up in Mississippi.
I have rebuilt a couple of these with the help of the people from the link provided. Lots of information there on this particular amp.
Unfortunately I understand even less about electronics than I do about women. At least I know enough to leave electronics to the professionals!
I get it. I'm not all that knowledgeable but I'm not afraid to go inside an amp and replace some parts, especially with the help of the nice folks here and the other site mentioned. Good luck.
If you get really desperate, you could always send it halfway around the world, to these guys. Damn shame they’re so far away, but still worth a read..
Some maintenance is 'sometimes' required on vintage equipment, that I can agree on.
However, you've obviously been reading internet blogs about "recapping" equipment, which in my opinion has been wildly overblown and spread around the internet like bird seed, and highly annoying to me - as a 45+ year audio/video bench tech.
In some cases, going for such 'surgery' is more touble than it's worth.
You stated "the amp works perfectly' - I'd maybe have the bias checked, perhaps some internal cleaning of controls, but don't fall for all that recapping nonsense unless an honest, reputable bench technician familier with the AU-717 actually shows signs of needing come caps replaced.
My previous comments are not really opinions, instead it's based on 45 years of experience professionally servicing these types of equipment.
Certified, now retired, I've got my certificates hanging on the wall, and plenty of pleased customers giving me a great reputation.
I've had thousands of customers walk though the shop's doors, and 10's of thousands of pieces of equipment on my service bench.
All brands, types, and conditions.
That gives me a pretty good idea of things, wouldn't you say?
And I will say that there are some good, decent other "repair people" noted on the internet, along with hoardes of others that spout nonsense too.
Good luck with that amp.
Assuming all the supply filtering and decoupling caps are ok as they do beneffit more of some formating current , you could consider changing the series coupling caps found in the signal path with the equivalent bipolar value from Nichicon muse(the metallic green ones) .For example, for two caps of 100uF/6.3v in series you'll use one bipolar capacitor of 47uF/16 or 25v... For two capacitors of 47uF/25V in series, you'd be using a single bipolar nichicon muse of 22uF/50V, for two csps of 10uF/25v you'll use one single bipolar capacitor of 4.7uF/50V and so on...half the value of each capacitor, double the voltage.Start with replacing only the electrolitic capacitors found in the signal path. Being two in series there's a great chance there's barely any dc current circulating through them, thus a greater chance of loosing their properties over time.They look like those in the picture attached:
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It wasn't to be... :-D
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It wasn't to be... :-D
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There were two amplifiers with similar approach : Sansui AU919 and Kenwood l-08M.Both super fast, tight, powerful amplifiers, basically the fastest VFB power audio amplifiers for at least 3 decades.
Yes, even the experienced have lots of opinions, from doing a full re-cap to just fix what is wrong, I'm in the camp of if it's not broken, don't fix it.
However, the AU717 amps, AU-517 and other Sansui, are notorious for having issues mainly due some goop used to hold the caps in place. Eventually over the years this goop corroded anything it touched, from caps to diodes and resistors. F2721 and F2722 (left and right channel) boards and the power supply board on the AU-717 were mainly affected by this which eventually made the amps inoperable or not run properly. Once the faulty components were replaced and the goop cleaned from the boards, doing the typical adjustments would bring these back to life, of course, unless there was another issue. I'm curious to know how this particular amp works out after it has "gone through".
Keep us posted and best of luck.
I fully agree with wiseoldtech about the recapping topic.