Tube Amps / Music Electronics
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|previous: Leo Padron I'm almost sure that I'm close to h... -- 7/15/1999 2:08 PM||View Thread|
|7/15/1999 4:11 PM|
|Dave H.||Re: Fender Pro clone 5e5|
It looks like you have the dreaded HF parasitic oscillation. It may not just be in the pre-amp. The parasitic feedback loop could be around both the pre and power amps. When you adjust the tone and vol controls you are changing the phase and gain in the loop which will change the frequency and amplitude of the oscillation. The "pop" is probably caused by the DC operating point of the amp shifting as it bursts into oscillation. Changing from 12AX7 to 12AY7 will give less gain which may stop the oscillation but I wouldn’t bet on it. You will probably have to re-route a few sensitive wires and or use some screened cable. Find the wires that change the frequency or amplitude of the oscillation when you move them about with a chicken stick (non conducting probe). Re-routing these wires may fix it.
|Leo Padron I did a little reading, and this so... -- 7/15/1999 4:42 PM|