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Gibson Chet Atkins PreAmp help
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Gibson Chet Atkins PreAmp help
Hey all, wondering if any electronics wizards out there might have any insights on an ’88 Gibson Chet Atkins. I do not have the guitar in my shop, but the owner has described the problem thusly…
“it sounds like it’s over driven or the battery is worn out when I plug it in to a board directly and play it with very little output.. and also.. it will not work through a direct box.”
He has already had it looked at by another reputable shop more than once. Apparently some caps and resistors were swapped, but almost no improvement was made. He did say there that there had been some intermittent popping sounds (possibly static discharge?) that did resolve.
Would appreciate any thoughts, comments, or tips, or a referral to someone who is well versed in active electronics in the northeast or anywhere in the US. The guitar is quite special to the customer and he does not want to give up on it.
Thanks for taking a look. I’ve attached some pics.
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3 Replies
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While I’m unfamiliar with the circuit itself, if the guitar were in my shop I’d start troubleshooting by making sure the battery was actually fresh. From there, I’d take my multimeter and check voltages throughout the circuit, making sure the transistor and IC and both getting power for example. You could also make yourself an audio probe and go through the circuit and see where the signal starts to weaken or distort. It could be that there’s a component failure, a broken connection or a solder joint that needs to be reheated. Going step by step through the circuit and being deliberate should yield results.
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Hi David! Thanks for the tips! Sounds like great advice for dealing with active circuits. I will give it a try if I get it in the shop. Much appreciated!
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Just my 2 cents: I would swap out the opamp IC – If they already thought of that, then never mind. The distortion is a clue. opamps that have had static discharge damage may appear to be perfectly fine when new. The damage often doesn’t rear its ugly head until years later, when the damage actually causes failure. It’s like a time bomb. I’ve seen it several times.
Other than that, cold or bad solder joints on the board can also fail after a long time. Remelting them usually helps.
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