Sansui amplifier volume control seized - worth repairing?

[Captain Jack Sparrow]

Hi guys,

I have a Sansui amplifier from (approx) the mid 1970s. Originally a transformer manufacturer, they manufactured this basic entry level amplifier. It's a model AU-2200 with a rated output of 15W per channel (but sounds like a LOT more, and via the headphone jack, it can be used as a pre-amp for a power amp). Here's an image of the unit, taken from the official service manual:

The sound it produces is fantastic, regardless whether it's through speakers, headphones or when it's acting as a pre-amp for my big-ass DJ speaker system. I also like its simplistic design, it does look damn handsome.

I really don't want to lose this unit, it has served me very well for over 6 years since I discovered it in the attic.
Things really were built-to-last around this time, not like today's cheap Chinese biscuit tin amps. On eBay, Sansui amps sell quickly, and fetch quite a substantial amount, so it's not easy to pick up a replacement.

The problem with this amp is that the volume control (the big control underneath the power LED) became very hard to turn last night and crackled a lot. This morning, it has completely seized up and it's stuck on the lowest volume setting. Of course, this yields no sound!!!
The amplifier should be okay electrically, as it was working fine before this happened, and still seems to power up without any issues.

Do you think it's worth repairing? It is only specified for 15W per channel, however I expect that due to its age, the output capacity may have deteriorated. But the sound quality from this was beautiful, and I know that if I bought a modern amp, I could not expect it to sound anywhere near as good as the AU-2200 for a reasonable price.

What are your thoughts on this? Has anybody attempted a basic repair here, and if so, how did you go about it?
Have you had amplifiers like these serviced? If you have, how much did it cost and where from? If I can repair this, servicing it afterwards would probably be a good idea. London Sound looks to me like a good, honest service provider, even if their website is horrible!

Let me know what you think.

- Capt. Jack Sparrow.

 

[muckshifter]

Send it to FBS.

joking aside, yes, I'd get it 'repaired' probable an easy job if you can get the part.

 

[Urmas]

http://www.manualslib.com/manual/887783/Sansui-Au-2200.html#manual

http://www.instructables.com/id/How-to-Build-a-Time-Machine-Vortex-Distortion-Spa/

 

[Becky]

Agreed that @floppybootstomp is the best man for advice on this

Hope you manage to get it sorted, it looks like a nice bit of kit!

 

[floppybootstomp]

Yes, it's worth repairing, imo.

Those are great little amplifiers and to quote the old adage 'they don't make 'em like that anymore'.

My brother-in-law had one of those in 1971 so I went out and bought one for myself, used it with a pair of Wharfedale Denton loudspeakers and had it for years until it got nicked from a basement flat I was living in which was burgled.

It's quite an easy repair if you're comfortable soldering, all you need is a twin pot of the same value, fit it (one nut) then make six solder connections. It will probably be about 50K log x 2.

If you don't feel confident making the repair yourself I'm in Greenwich SE London or find a local place to have it fixed, I think it would be worth it.

EDIT: An amplifiers' output power won't deteriorate over time. The sound quality may get worse and volume controls will fail (they're a mechanical device) but other than that an amplifier will usually just work or not work.

Power ratings are overrated. I'm using 7 watts per channel on my main sound system atm and it's plenty, the bass response can certainly make the floor vibrate

 

[floppybootstomp]

Edit # 2: The repair place you've linked to, as far as I know, are good. I once phoned them up about a Quad pre-amp and ended up talking to the geezer for over an hour, he's a real enthusiast. My gut feeling says he wouldn't rip you off.

And in my opinion you can't really service an audio amplifier apart from squirting a little Servisol into the pots. It's also wise to replace the electrolytic capacitors after 10 - 15 years as they do deteriorate over time and their worsening can degrade the sound.

 

[Captain Jack Sparrow]

Edit # 2: The repair place you've linked to, as far as I know, are good. I once phoned them up about a Quad pre-amp and ended up talking to the geezer for over an hour, he's a real enthusiast. My gut feeling says he wouldn't rip you off.

And in my opinion you can't really service an audio amplifier apart from squirting a little Servisol into the pots. It's also wise to replace the electrolytic capacitors after 10 - 15 years as they do deteriorate over time and their worsening can degrade the sound.

That gives me faith! I shall give him a call when I get back from the holiday.

Also when I get back, I'll open the bonnet of the amp, and see how hard it is to get the volume control board out. I may be able to desolder the part and find a suitable replacement. Hopefully this won't be too difficult.

But yeah, that's what I meant when I said service the amp. The capacitors really should be replaced, even though the amp was working okay. It says on his website, he will not undertake complete capacitor replacement, he will only replace the components which have fallen outside of their specification. I rekon as "service" he means he checks all the components to make sure that they are within specification, otherwise he replaces them. He sounds like a really sound guy! GET IT?

- Capt. Jack Sparrow.

 

[Becky]

He sounds like a really sound guy! GET IT?

Ba-dum tsssssss