I have a Harman Kardon 330A stereo receiver, bought it new around 1973 or 1974. I love it . Problem is now the sound is distorted in one of the two channels . Can anyone tell me what is most likely the problem and where can I get parts to repair it. Thanks
It is not easy to tell with the information you provide where is the problem, the nature of it and how to resolve it. Distortion in audio is the result of many different problems that may be happening at different stages of the system. I assume you don't have any instruments to test the signal at different points.
The most common problem (in my experience) is a contact problem that can be fixed by using a "GOOD" contact cleaner in every switch (in the audio path) and potentiometers. If this does not resolve the issue then I would try to determine if it is common in all the inputs or just in one. If it happens in all then we can be going any further and precise the point of testing on the amplifier module. Again, as I can't say how hard the distorition is, and what is really distorted (could be a noise, a cicle cuted or a cross distortion...or even more) there are many parts that could be damaged, one of the most common issues is a problem with capacitors (I am talking in a general way) after so many years, the capacitor, is becoming dry and looses not only its capacity but also the ESR value increases, and could be causing a bad feedback or coupling, or even bad voltage stabilization at some point, but this is more theory than your amp's specific design.
Try to get more information as much as you can and DO NOT replace all capacitors as most people often suggest, probably, depending on where you purchase them, you'll get worser capacitors than the ones installed despite how old they are.
The most common problem (in my experience) is a contact problem that can be fixed by using a "GOOD" contact cleaner in every switch (in the audio path) and potentiometers. If this does not resolve the issue then I would try to determine if it is common in all the inputs or just in one. If it happens in all then we can be going any further and precise the point of testing on the amplifier module. Again, as I can't say how hard the distorition is, and what is really distorted (could be a noise, a cicle cuted or a cross distortion...or even more) there are many parts that could be damaged, one of the most common issues is a problem with capacitors (I am talking in a general way) after so many years, the capacitor, is becoming dry and looses not only its capacity but also the ESR value increases, and could be causing a bad feedback or coupling, or even bad voltage stabilization at some point, but this is more theory than your amp's specific design.
Try to get more information as much as you can and DO NOT replace all capacitors as most people often suggest, probably, depending on where you purchase them, you'll get worser capacitors than the ones installed despite how old they are.
Agree with comments from cqtsdss, problem could be anywhere. More diagnostics
would be helpful. Run the HK as a separate, ie, use it as a preamp/power amp
via the pre-out/main in RCA's. Certainly try the other inputs (tuner/phono/aux...)
Try connecting speakers to "System 2" (may be dirty speaker selector).
Check if distortion present when using headphones.
would be helpful. Run the HK as a separate, ie, use it as a preamp/power amp
via the pre-out/main in RCA's. Certainly try the other inputs (tuner/phono/aux...)
Try connecting speakers to "System 2" (may be dirty speaker selector).
Check if distortion present when using headphones.
If you remove the amplifier link leads and insert a known clean signal, that will tell you if the problem is output or pre amp related.
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