CD Player with one bad channel

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I've been lucky enough to be given a Sugden CD Master. The problem is that the left channel is outputting a very low volume, highly distorted signal. The original owner has been of no use since his diagnosis was 'it went whacky one day so I want rid of it'.

I've checked the transport by connecting the player's digital out to a DAC and everything is fine. Nothing looks fried or lose inside the case.

So I have two questions. Firstly does anyone have any suggestions as to the source of this type of problem and secondly is this a repair that someone with reasonable, if very outdated skills could tackle.

Thanks

Gary
 
Is it the Master or Masterclass ?

It could be the output op-amp gone duff or a dry/bad joint in that area esp. the muting transistors.

The easiest way to track down the fault is with a small amplifier and test probes plus a multimeter.

Check the voltages on each pin of the opamp comparing good and bad channel.
If they are both OK, then use tha amplifier probe from the output back til you get sound.

Andy
 
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If it uses a relay to mute and short the output to ground it could be that. If it was stuck "short" it's surprising to say a signal may still appear but it might if the relay has a little contact resistance and it would give that symptom.
Whatever it is it can't be much :)
 
Hey--I have a TEAC 1260 cd player--bought new in 2010-- barely used at all--that has the same problem--one channel barely audible. It is a few months past warranty. I don't know where to begin--I have two other nice looking but dead cd players and it's getting tiresome!
 
I know it's been a while now (nearly 10 years!) but did you ever solve this problem? I have a Technics CD player, had since the mid 90s, which now does a similar thing: intermittent problem with the right channel; broken and distorted sound but it can clear up temporarily when I twist the phono plugs a bit at the output.
 
: intermittent problem with the right channel; broken and distorted sound but it can clear up temporarily when I twist the phono plugs a bit at the output.
Often the RCA/phono jacks are soldered directly into the PCB.
I'd check those solder joints for a start.
I've seen similar problems with DC power jacks and 3.5 mm headphone/line jacks sometimes.
If you are lucky, you will be able to get at the bottom (solder side) of the board easily. If not, it can be a bit of time to access, for what is a 1 minute solder touch-up.:)
 
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