Hi.
So I have a Technics SU-Z450 stereo amplifier that I have been using for a few years now. The other day I started to listen to my turntable and I noticed that the right channel was significantly quieter than the left channel. I tried reversing the speakers (plugging the left speaker into the right output), reversing the connections to the turntable, adjusting the balance control and I also tried other inputs on the amplifier but to no avail; the right channel remained significantly quieter than the left channel.
I don't know how to go about fixing this issue.
Any help is much appreciated.
So I have a Technics SU-Z450 stereo amplifier that I have been using for a few years now. The other day I started to listen to my turntable and I noticed that the right channel was significantly quieter than the left channel. I tried reversing the speakers (plugging the left speaker into the right output), reversing the connections to the turntable, adjusting the balance control and I also tried other inputs on the amplifier but to no avail; the right channel remained significantly quieter than the left channel.
I don't know how to go about fixing this issue.
Any help is much appreciated.
First try a contact cleaner such as Caig Labs DeoxIT on all the switches, pots, etc.
Especially check the tape monitor and speaker switches. If you can't do that,
push the switches in and out several times, listening for an erratic contact.
Last edited:
Thanks for the quick reply.
I don't have any contact cleaner so I'll go out and get some as soon as I can.
I don't have any contact cleaner so I'll go out and get some as soon as I can.
Try pushing the switches first and see if one seems flaky. Sometimes all of them are.
Agreed about Technics switches. The small signal switches, particularly the miniature push on/off types, have silver plated contacts and they do go bad - real bad, like no contact at all, noisy etc. If you have say, muting, CD direct or tone bypass switches, check and lube them carefully as they are usually PCB mounted and splashing solvent over the rest of the electronics isn't a good idea.
Hi dnlfern,
I'll add to this.
#1, push each switch in slowly one at a time. Write down your results. Then, rotate the volume, balance, tone etc ... and once again note the results. If you operate the controls quickly, you can temporarily "fix" the problem. The tape monitor switch is the most likely to cause trouble, the loudness switch after that.
Cleaning sprays. Try not to use them. Use as little as possible to correct the problem and don't "spray" any other controls or switches. This stuff is a cleaner and it also cleans the protective lubricant out of the device. Same for the bearings in controls.
For a control, like a volume or balance, a dripper is best. It is the slip ring and fingers that becomes noisy, not the carbon track! Apply a little cleaner on the slip ring and that normally cures your problem right away. With slide controls, it is critical you don't wash the special lubricants out by spraying. One track is your carbon, the other is the sliding contact. Double for stereo controls. Clean the sliding contact and the control will also retain its feel.
Spraying controls is a lazy habit we have to ween ourselves from doing. Most people figure that spraying everything with a good soak is doing a good job. Nope. You are hurting the customer down the road by doing that.
Note that Technics sets seem to suffer from bad solder connections on any component that attaches to the heat sink or the rear panel. Same for the contacts for the plug in boards. If this set has a fan, pay special attention to the contacts for it.
-Chris
I'll add to this.
#1, push each switch in slowly one at a time. Write down your results. Then, rotate the volume, balance, tone etc ... and once again note the results. If you operate the controls quickly, you can temporarily "fix" the problem. The tape monitor switch is the most likely to cause trouble, the loudness switch after that.
Cleaning sprays. Try not to use them. Use as little as possible to correct the problem and don't "spray" any other controls or switches. This stuff is a cleaner and it also cleans the protective lubricant out of the device. Same for the bearings in controls.
For a control, like a volume or balance, a dripper is best. It is the slip ring and fingers that becomes noisy, not the carbon track! Apply a little cleaner on the slip ring and that normally cures your problem right away. With slide controls, it is critical you don't wash the special lubricants out by spraying. One track is your carbon, the other is the sliding contact. Double for stereo controls. Clean the sliding contact and the control will also retain its feel.
Spraying controls is a lazy habit we have to ween ourselves from doing. Most people figure that spraying everything with a good soak is doing a good job. Nope. You are hurting the customer down the road by doing that.
Note that Technics sets seem to suffer from bad solder connections on any component that attaches to the heat sink or the rear panel. Same for the contacts for the plug in boards. If this set has a fan, pay special attention to the contacts for it.
-Chris
- Status
- Not open for further replies.