Remember
the HH VS Bassamp 100 115 Combo
So I've been asked to play bass tonight. I've been and bought a sack barrow so I don't have to carry it everywhere:
- argos_trolley.jpg (9.66 KiB) Viewed 18 times
I found when I plugged it in after a few years in the garage that it was noisy and a bit dodgy. I sprayed all the pots and jack sockets with Servisol and that fixed most of the dodginess, leaving me with noise like a Fuzz Face through the high gain channel of an amp turned up to 6. None of the controls made any difference, so I tried plugging in to the Echo Return and putting a plug in Echo Send to disconnect the preamp. No difference. So all this noise was coming from the power amp board.
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So, remembering that I have had the odd noisy op-amp in an HH before, I suspected the 741, IC1.
- SFC2741DC.jpg (193.86 KiB) Viewed 18 times
Fortunately, I had an NE5534 low noise drop-in replacement and an 8-pin turned-pin socket, so I fitted those. The NE5534 also has a slightly higher maximum supply voltage, which gives me a bit more safety margin when the rails are +/- 18 V
- Socket.jpg (188.61 KiB) Viewed 18 times
Result; I wasn't sure the speaker was plugged in until I turned the master volume up full and heard a faint hum. Amazing. I might do that on all 3 of my other HHs.
