[Help needed] One amplifier channel not working properly

[Nathan44]

Hi there!
I got an old turntable setup from my dad and I'm trying to get it working again. One of the problems is with the amplifier. Namely the sound from the left channel does either not work or is having trouble creating sound. I already scowered through some forums trying to find a solution, but I wasn't able to realy find a conclusion on it, so I'm hoping someone here can help me clear things up.

It's about the Philips 22AH683 amplifier and these are some of my observations:
-It is the amplifier not something else: I tried different different sources and different output devices
-It is always the left channel, switching the source cables left and right changes nothing and using stereo or mono also has no effect
-Increasing the volume on the amplifier while decreasing the source volume sometimes helps, where it goes from no sound on the left channel, to a distorted sound, to a good sound.
-Using the bass and treble buttons: the lower frequencies are mostly distorted and the higher frequencies are damped.
-Turning the bass and treble potentiometers does not create any crickling sound
-Twisting the volume knob like crazy may help a little with going from no sound to the distorted sound

I mostly read about cleaning/replacing the potentiometers or the relais, or that it might be any condensator. I don't mind replacing any components, but I also don't want to waste money on replacing the wrong ones and eventually still not fixing it. So does anyone have a clear idea of what it could be or am I better off handing it over to a repair shop? Anyway thanks for reading through all that and for any answers

 

[spark1]

Clean all of the pots and switches. Deoxit D5 for switches, Faderlube for pots.

Then let's see where you are with it. Much too early in the process to talk about parts replacements, which should always be preceded by a specific diagnosis, which in turn is preceded by step by step troubleshooting.

 

[Nathan44]

Clean all of the pots and switches. Deoxit D5 for switches, Faderlube for pots.

Then let's see where you are with it. Much too early in the process to talk about parts replacements, which should always be preceded by a specific diagnosis, which in turn is preceded by step by step troubleshooting.

Fair enough, I'll try cleaning them soon. But I only have contact cleaner, I hope that would do the trick. Because I don't use specific sprays enough to be worth buying.

 

[spark1]

I'm leery of it on pots. Others may have a different opinion.

 

[cademan]

Clean relay contacts if it has one.

 

[spark1]

Clean relay contacts only if cleaning pots/switches doesn’t work.

The relay contacts are very delicate (thin plating). If you do end up doing it, try using a strip of paper soaked in Deoxit (or contact cleaner, in your situation).

If it requires more aggressive cleaning, you can try very, very fine sandpaper (1000, or even 1200-1500). In my limited experience, this may solve a problem of spotty connectivity, but will almost surely accelerate the demise of the relay.

 

[Ray Gianelli]

I'm leery of it on pots. Others may have a different opinion.

I'm with you. Nothing gets sprayed in pots on my bench except for Faderlube F-5.

I suspect that if a cleaner is marked plastic safe it would by OK in pots. But since these parts are obsolete and you're at the mercy of eBay I err on the side of caution.

 

[andromediamn]

When cleaning relays, I usually spray some cleaner on a strip cut out from a paper coffee filter, then with mild pressure on the reeds, pull the wet filter paper through. The filter paper holds up better, doesn't tear as easily and has a rough-ish texture to pull the dirt off the contacts.

 

[CES_Engineer]

Hi there!
I got an old turntable setup from my dad and I'm trying to get it working again. One of the problems is with the amplifier. Namely the sound from the left channel does either not work or is having trouble creating sound. I already scowered through some forums trying to find a solution, but I wasn't able to realy find a conclusion on it, so I'm hoping someone here can help me clear things up.

It's about the Philips 22AH683 amplifier and these are some of my observations:
-It is the amplifier not something else: I tried different different sources and different output devices
-It is always the left channel, switching the source cables left and right changes nothing and using stereo or mono also has no effect
-Increasing the volume on the amplifier while decreasing the source volume sometimes helps, where it goes from no sound on the left channel, to a distorted sound, to a good sound.
-Using the bass and treble buttons: the lower frequencies are mostly distorted and the higher frequencies are damped.
-Turning the bass and treble potentiometers does not create any crickling sound
-Twisting the volume knob like crazy may help a little with going from no sound to the distorted sound

I mostly read about cleaning/replacing the potentiometers or the relais, or that it might be any condensator. I don't mind replacing any components, but I also don't want to waste money on replacing the wrong ones and eventually still not fixing it. So does anyone have a clear idea of what it could be or am I better off handing it over to a repair shop? Anyway thanks for reading through all that and for any answers

Are you still looking for help with this problem? Used to work for Philips Elecronics as an audio repair engineer and know these amps very well.