Hello. I have an Aragon 24K preamp that has a little scratchiness in the volume control in the first 1/4 turn on the left channel. I had a cheap linear pot. so I stuck that in circuit and it did the same thing. I took the original Noble pot. apart and cleaned it. It's fine.
I did measure -49mv across each the sliders to ground. I did stop all the noise by soldering in a couple of 4.7uF NP caps in series with the slider.
There are a couple trimmers close to the line amp. I was wondering maybe these are offset adjusts.
For ref: power supply output: -24.70 and +25.32
Thanks all! I am stumped....
I did measure -49mv across each the sliders to ground. I did stop all the noise by soldering in a couple of 4.7uF NP caps in series with the slider.
There are a couple trimmers close to the line amp. I was wondering maybe these are offset adjusts.
For ref: power supply output: -24.70 and +25.32
Thanks all! I am stumped....
Sounds like input bias current of the following amplifier stage is at fault, which would indicate either a leaky existing coupling cap or none being present at all (which would be a design issue). It's hard to tell more without a decent idea of what the circuit looks like. Seems to be a discrete affair.
Hi Rick,
I need the aragon 24K schematic...I would really, really appreciate it.
rgor2@juno.com
Thanks, Roger
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