I have on my workbench '74 Ampeg V4 non-master volume model which acts weird... This amp has two completely separate channels, each one is driven by its own 12AX7.
It's something I can't understand. When I plug into CH#2 everything is fine, but when I plug into CH#1 sound is quiet and distorted, gets louder and better when... channel 2 volume is turned up. I have resoldered connections on the pcb of both channels but nothing changed.
In basic words
1. When I plug into CH#1 - both CH#1 and CH#2 volume pots are working and interacting with each other
2. When I plug into CH#2 only CH#2 volume works (so as it should).
Any ideas?
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Size: 5.84 MB
ID: 876158](filedata/fetch?id=876158&d=1649410203)
It's something I can't understand. When I plug into CH#2 everything is fine, but when I plug into CH#1 sound is quiet and distorted, gets louder and better when... channel 2 volume is turned up. I have resoldered connections on the pcb of both channels but nothing changed.
In basic words
1. When I plug into CH#1 - both CH#1 and CH#2 volume pots are working and interacting with each other
2. When I plug into CH#2 only CH#2 volume works (so as it should).
Any ideas?
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