eduarsan1
Luis Eduardo Sanchez
Guys I need your wisdom
6 Months ago I got a 500K control volume from Mark Oppat and last week the left channel starts to be noisy like scratching between min. and 9 o´clock and then I asked to Mark about the pot and here is their answer:
"Hi Luis,
Remember that sometimes the control is not the actual problem, and I doubt it is here either. These do not “age” that fast so for this item to change in that time is nearly impossible. Have you recapped that unit? Also tubes will cause this issue too, even though you think the control is at fault.
I know you think it can not be, but believe me, capacitors and tubes will exhibit this condition.
Here is a simple test:
Reverse the leads on the center terminal of the control. That is, take each center lug wire and move it to other section of the control. If the problem moves over to the other channel, the issue is from the control back to the input of the unit. If it STAYS on the same side, the problem is AFTER the control thru to the output stage.
I think you will find your problem this way."
The amp is a Fisher 400 fully restored with IBAM, EFB, coupling caps and tubes as well.
Thoughts??
Honestly IMHO I think is a quality issue on the pot
Regards
Luis
6 Months ago I got a 500K control volume from Mark Oppat and last week the left channel starts to be noisy like scratching between min. and 9 o´clock and then I asked to Mark about the pot and here is their answer:
"Hi Luis,
Remember that sometimes the control is not the actual problem, and I doubt it is here either. These do not “age” that fast so for this item to change in that time is nearly impossible. Have you recapped that unit? Also tubes will cause this issue too, even though you think the control is at fault.
I know you think it can not be, but believe me, capacitors and tubes will exhibit this condition.
Here is a simple test:
Reverse the leads on the center terminal of the control. That is, take each center lug wire and move it to other section of the control. If the problem moves over to the other channel, the issue is from the control back to the input of the unit. If it STAYS on the same side, the problem is AFTER the control thru to the output stage.
I think you will find your problem this way."
The amp is a Fisher 400 fully restored with IBAM, EFB, coupling caps and tubes as well.
Thoughts??
Honestly IMHO I think is a quality issue on the pot
Regards
Luis