1974x static issue

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foreverstrung
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1974x static issue

Post by foreverstrung »

My 1974x reissue started spittin some static about 3 days ago. It's only a bedroom player, so min use. I tried swapping out the pre amp tubes. Considering the el84's, but thought I'd put it out here for direction before taking it to the tech.
I installed an new PT a few months ago. Since then it's been beautiful. Just the last few days.
Unplugged pedal board and had guitar direct and still static. Changed cable and still and then I unplugged the guitar completely and STILL static.
appreciate any help
TIA
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Re: 1974x static issue

Post by Unit_1 »

foreverstrung wrote:
Wed 05/25/22 9:25 pm
My 1974x reissue started spittin some static about 3 days ago. It's only a bedroom player, so min use. I tried swapping out the pre amp tubes. Considering the el84's, but thought I'd put it out here for direction before taking it to the tech.
I installed an new PT a few months ago. Since then it's been beautiful. Just the last few days.
Unplugged pedal board and had guitar direct and still static. Changed cable and still and then I unplugged the guitar completely and STILL static.
appreciate any help
TIA
Have you tried wiggling the pots? Just take each one and go from zero to max back and forth a few times with the amp on so you can hear it if it crackles. Many times on amps and guitars the pots can get dirty from dust in the air or like that stuff that forms on the inside of your car windshield.

If you hit one that crackles when you wiggle it, agitate it at the noisiest point until the sound fades. Had this happen to me last week on my JTM50 I built. It was the presence. Wiggling helped but I had to give the pot a squirt of DeOxit d5, wiggle, wait a few, another squirt and bingo, silence....
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Bieworm
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Re: 1974x static issue

Post by Bieworm »

Static ... big chance it's the power tubes or rectifier tube. Avoid JJ tubes on those at ANY cost.
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foreverstrung
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Re: 1974x static issue

Post by foreverstrung »

Thanks for all of that. Good stuff. I've got a couple matched sets of el84's. and dirty pots sound like a good place to start........and to clarify, it is more of a crackling than static.
Appreciate it
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Bieworm
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Re: 1974x static issue

Post by Bieworm »

Crackling is tubes or bad solder connections. Or a broken component. Pots don't relate to this IMHO
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Re: 1974x static issue

Post by JMPGuitars »

DC on the pots can sometimes sound like crackling. This could be caused by a leaky capacitor.
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foreverstrung
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Re: 1974x static issue

Post by foreverstrung »

Looks like the EL84's. I swapped them out and the crackling is not present. However the volume and tone knobs on the Tremolo channel are a little "scratchy". Not over the top, but still. Any suggestions on cleaning?
thx
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Re: 1974x static issue

Post by Daviedawg »

Yes clean them with contact cleaner sprayed into the pots. Twiddle the knobs to clean the traces. Different pots have different ways in.

Then if still noisy, check by measuring for DC voltage between the pots and ground. If you find DC you need to trace it back to a capacitor which is leaking.

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