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Best choice circa £200-300 uk and what to avoid?

ziggydave said:
I meant something you should never do is power up without speakers or some sort of load connected.
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This is correct for Valve amplifiers because you can damage Output Transformers and Output Valves by NOT connecting speakers. As said the opposite is true for 'Direct Coupled' SS amplifiers where a very common fault condition (high DC offset), could damage the connected speakers, and cause even more damage to the already faulty output stage. Although luckily, the protection circuit used in the majority of these amplifier types weeds out many speaker killing 'opportunities'. :rolleyes: Many people who power up unknown amplifiers a lot keep a set of 'beater speakers' to use when they are not sure if an amplifier has this kind of fault or not.

The reason why people state that they don't have any speakers (LOL) - or haven't tested the amplifier with same, is because they don't want to clearly state that the amplifier works fine. Why? because if it doesn't, maybe though no fault of their own (e.g. new owner connects speakers with power on and shorts terminals in the process), they (theoretically), can't be hit with 'not as described' claims. :)
 
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Hyperion said:
This is correct for Valve amplifiers because you can damage Output Transformers and Output Valves by NOT connecting speakers. As said the opposite is true for 'Direct Coupled' SS amplifiers where a very common fault condition (high DC offset), could damage the connected speakers, and cause even more damage to the already faulty output stage.
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Well, every day is a school day John, thanks for the advice!
 
Goodaye all

l have a pair of crappy speakers used for testing any amp, l usally leave them running for a couple of hours after any work.
Did burn out one of a pair once.

Also l use a old mp3 player as a source while l have the cover off and adjusting.
Just in case.

regards Bruce
 
Yo
Sloper1940 said:
Goodaye all

l have a pair of crappy speakers used for testing any amp, l usally leave them running for a couple of hours after any work.
Did burn out one of a pair once.

Also l use a old mp3 player as a source while l have the cover off and adjusting.
Just in case.

regards Bruce
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You mean a faulty amp can wreck an input source too? It's a bit of a gamble this old gear hunt, isn't it!
 
Back to picking up old amps, this week a procured a Sansui R7 receiver as part of a lot. (It cost me nothing, the power switch wasn't working, it had fallen inside, an easy fix.) I've cleaned it up and cleaned the pots etc, and it is fully functional and sounds great I must say. It obviously isn't in the same generation as the AU 317, the build quality is much lighter, but it is a fine-looking piece of kit nonetheless, actually showroom condition. It had been in a cabinet all its life, one owner, and was absolutely filthy but otherwise undamaged. It has a particularly quirky touch control for volume with a powered operation, very strange, but it works flawlessly so I suppose it has proven its design.

I can't find another on fleabay, so I guess they either weren't popular or don't normally last. Is anybody familiar with the R7?
 
Just to finish the thread, I can report that the Au317, after servicing (£40), the engineer reports all voltages bang on original spec. He said it was a pleasure to work on. With all the pots and switches now completely crackle-free, it's just beautiful and awesome-sounding, so thank you to everyone who helped me find it!
 
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