• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Help Needed with Conrad Johnson PV-8 Preamp Knob noises and gain bleed

I

Ignaciog

New Member
Hello everyone,

I've recently acquired a used Conrad Johnson PV-8 preamplifier. While I'm thrilled with its performance, I've encountered an issue where adjusting the volume, balance, and channel knobs results in a crackling noise. This crackling is especially bothersome with the volume control, as it bleeds when i try to bring it to lower levels, making it challenging during quieter social settings where conversation needs to be clear.
Could anyone here offer some advice on how to address this? Also, if anyone knows of a good repair service in NYC or has the expertise to take a look at audio gear in their spare time, I'd greatly appreciate the information.
Looking forward to your insights.
Best regards,
Ignacio
Post





audio equipment maintenance
more technical details
 
Last edited:
Register to hide this ad
I'd start by squirting a shot or two of DeoxIT D5 or other contact spray cleaner into each pot and turn it back and forth several dozen times. Do that twice and then hit it with a final spray to wash out any remaining debris. If you really want to give it the royal treatment, use DeoxIT FaderLube as the final spray. Place a paper towel around the pot as you are spraying to avoid any overspray on the rest of the chassis.

Depending on where you live there might be someone who would offer to look at it.
 
It's kinda silly to ask for hands-on help without including your location. About the Deoxit, note that overuse of contact cleaner can wash the lubricant out and create a very poor feel to the control. Back in the day, MCM used to sell tubes of clear grease called Tunerlube. If a dry control was heated, this grease would thin and wick into the space between the shaft and bushing. When it cooled back to room temperature, the control would have a factory feel again.

Jack
 
I refreshed a PV5 last year and had to Deoxit the controls. I just looked at pics of the PV8 guts and its pretty similar. It's easy enough to do the balance pot but the volume pot is mostly sealed. Im trying to remember how I did it but think I took the knob off, stood the unit upright and tried to dribble some Deoxit down the shaft before working the knob. Changing out the 2 small electrolytics fixed a hum issue I was having. Cleaning the speaker relay fixed the sound bleeding through issues it was having.
 
Ignaciog said:
Hello everyone,

I've recently acquired a used Conrad Johnson PV-8 preamplifier. While I'm thrilled with its performance, I've encountered an issue where adjusting the volume, balance, and channel knobs results in a crackling noise. This crackling is especially bothersome with the volume control, as it bleeds when i try to bring it to lower levels, making it challenging during quieter social settings where conversation needs to be clear.
Could anyone here offer some advice on how to address this? Also, if anyone knows of a good repair service in NYC or has the expertise to take a look at audio gear in their spare time, I'd greatly appreciate the information.
Looking forward to your insights.
Best regards,
Ignacio
Post





audio equipment maintenance
more technical details
Click to expand...
Just clean the controls….

I’ve had a couple of PV’s, all great units that sound excellent. Never hurts to replace the films, I wasn’t super impressed with the component selection.
 
if cleaning the controls doesn't get it sorted, leaky caps that put DC on the pots tends to make them noisy. No idea what the controls layout is on these without digging up a schematic but its worth a thought.


why does this have a weirdly spammy sort of feel to it, especially given the links to an AI interface for certain key words?
 
You must log in or register to reply here.
Back
Top Bottom