pre-amp noise when adjusting volume

[malibushirl]

I have a Kinergetics Chiro 802 Pre-amp and this weekend I
noticed that as I adjust the volume on the preamp it was making noice.

Never did this before and I have owned since 2001...what causes this, is there a fix or is this a precursor for other things to come?

Thanks all.

[markw]

That's a little general, there. Perhaps a spritz or two of contact cleaner into the volume pots?

[malibushirl]

Thank you for responding to my post:


>That's a little general, there.
I'll try to be a liitle more specific but not sure what else I can detail.

As I turn up the volume on the preamp, and I do it very slowly, I have noticed at higher amplified levels a slight click noise for each notch(volume level increase) I attempt.
Obviuously this sound gets louder as as the volume level is increased. There is no other noise when playing music or movies just the noise when I slowly adjust the volume.

Help me out, what other diagnostics or conditons should I be providing?

>Perhaps a spritz or two of contact cleaner into the volume pots?[/QUOTE]

Also, not famiar with term "Volume Pots". Are you refering to an input/output on the back of the pre-amp? If so which one or what would it normally be labeled?


>Perhaps a spritz or two of contact cleaner into the volume pots?[/QUOTE]

[Toga]

Hiya!

Over time, the signals that flow through open air switch contacts and level controls ("pot" is short for potentiometer) slowly plate them with atmospheric contaminants. It is a physical layer of accumulated dust, dirt, cooking soil and micro corrosion, all affected by the electrostatic potentials. Apparently, even a few hundred milivolts is all that is needed over a period of years. Luckily, several steps can be taken to improve things. The best controls are "sealed", but are extremely expensive.

One option is "exercising" the volume control. This is essentially the working back and forth through the noisy range with a bit more velocity than normal to "work loose" the deposits. Contact cleaner can help with the removal, but can also gather new dirt. If you have a tech you trust, take it to them for a rebuild. That is the actual removal of the control from the equipment, a careful teardown and cleaning, and reassembly. If the company that made the equipment still has stock, the purchase of a control that is brand new can also eliminate the problem. Keep the old control as a spare for the future.

From your description, you have a stepping switch set up to mimic a pot with many discrete switch contacts and fixed resistors. This is why you can hear the distinct clicks. Repair/cleaning will follow a similar course.

[malibushirl]

Awesome post! Thanks for expalining this in detail. Will contact the audio shop where I purchased a feww years back to see if they can repair/service.

-
Hiya!

Over time, the signals that flow through open air switch contacts and level controls ("pot" is short for potentiometer) slowly plate them with atmospheric contaminants. It is a physical layer of accumulated dust, dirt, cooking soil and micro corrosion, all affected by the electrostatic potentials. Apparently, even a few hundred milivolts is all that is needed over a period of years. Luckily, several steps can be taken to improve things. The best controls are "sealed", but are extremely expensive.

One option is "exercising" the volume control. This is essentially the working back and forth through the noisy range with a bit more velocity than normal to "work loose" the deposits. Contact cleaner can help with the removal, but can also gather new dirt. If you have a tech you trust, take it to them for a rebuild. That is the actual removal of the control from the equipment, a careful teardown and cleaning, and reassembly. If the company that made the equipment still has stock, the purchase of a control that is brand new can also eliminate the problem. Keep the old control as a spare for the future.

From your description, you have a stepping switch set up to mimic a pot with many discrete switch contacts and fixed resistors. This is why you can hear the distinct clicks. Repair/cleaning will follow a similar course.