PV 12A volume issues

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cavak
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PV 12A volume issues

Post by cavak »

Hi,
I have CJ PV 12A that has some issue with volume that is exhibited regardless of the input (line or phono). When the volume is turned down to 0 (min volume) , source music is audible on one of the channels. It seams that the same channel is little bit louder at higher volume levels. Is there anybody that has experienced the same issue ? What could the the problem ? Faulty volume control ? thanks
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admin
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Re: PV 12A volume issues

Post by admin »

As a PV12 owner myself, a couple of questions. Is your balance set to center? Can you make it go away with setting the balance to the other channel? It certainly could be something in the volume control, perhaps the amplification circuitry as well.
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Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
cavak
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Re: PV 12A volume issues

Post by cavak »

yes.. balance control is in the middle .. moving balance control to one side improves the situation
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admin
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Re: PV 12A volume issues

Post by admin »

If you have a multimeter, you could perhaps test the input and output resistance on the volume control unit and compare the two channels. Perhaps faulty resistor? I'm not great with electronics but it may be that. In the meantime, if the balance control improves the situation you can certainly use that. The maximum attenuation you can get with the PV12 balance control is 4 db if I recall correctly. Maybe that will be enough in which case there is no rush to fix the issue.
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Home Theater in Member Gallery
Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
kellyh
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Re: PV 12A volume issues

Post by kellyh »

I'm very late to this post, but my PV12 volume pot issues where a bit similar, erratic control (not scratchy though), and some volume when it was all the way down. Solved with advice from Jeff at CJ:

"Remove the top cover. Turn the preamp upside down. Spray DEOXIT D5 at the bottom of the volume control, where it mates against the circuit board. Turn the volume control back and forth gently a few times. Let the cleaner evaporate overnight. Clean up excess DEOXIT D5 with Q-TIPS."

Worked. I heard the PV12 has a carbon type of pot is is prone to getting dirty.
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