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This 70’s amp might be similar to a Champ. This particular one is quite noisy with “static” though. I put in new JJ tubes and it sounds awesome powering a cabinet with two Canabis Rex Eminence 12’s - but what is all that “static” coming out of it though? Are there any tube amp techs on this forum in the Kelowna area? Thanks for any info Jim
 
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I would first get a can of Deoxit and gently spray all the pots. There are usually a couple of small openings on the back of the potentiometer you can spray the Deoxit into. Then open and close the pot fully 20-40 times. I would also check that the input jacks and any other jacks are clean and tight. You can spray a 1/4" jack with the Deoxit and repeatedly plug and unplug the jack to clean the contact.

If the crackling is still there check the speaker wires and tubes. After that you will need one of the amp guys here to advise you further.
 

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There is also a possibility that it has carbon comp resistors that have become noisy as they age resulting in a drift of the resistance.

Another possibility is a leaking capacitor (or several).

How long was the amp in storage?
Was the static noise there when you last played through it?

The noise(s) could be be caused by one or more of several issues.

BE VERY CAREFUL if you working inside that amp. The capacitors can retain a lethal charge even with the amp turned off.

Hopefully you can find a local amp tech.
 

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That's a model I don't know much about. No schem in the Garnet book IIRC. Post pics inside and out if/when you can plz/thx.
 

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Is it a " sputtering" kind of "static"?

It might go away when the amp has been warmed up for a while.

However, the problem may still increase over time until the amp quits altogether.

My Garnet has been to Gar Gillies and later re-capped/etc by Mark Stephenson. Worked fine for them, but the problem was still there when the amp was returned (both times).

It got worse over the years and "sputtered" out completely last year. JBWelder got it going again. Thanks JB, great job!

But already the problem is returning slightly. I know nothing about electronics, but I am beginning to suspect some aspect of the design. It will probably be OK for the rest of my life. I just give it lots of warm-up time.

As Greco said: "Hope you can find a local amp tech".
 

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I'd love to see a picture of it. The Celebrity was my first "real" amp. Mine was a very compact single 12" combo with a single 6CA7/EL34 power tube.

Might have nothing to do with it, but the first thing I do with any old amp is clean the input jack.
 

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Aside from having known good/quiet tubes, ensuring the input sockets are clean, ensuring the tube sockets are tensioned and clean, ensuring the pots are clean, and that the unit is properly grounded, what we're most likely left with is component drift or failure (caps or resistors) causing suboptimal operating conditions. Poor/sloppy wiring or a lack of shielding can also result in noise and interference. A proper full service can/will address any and all of these issues for not very much scratch.
 

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If its a sizzling sputtering crackle I'd be willing to bet on there being a bunch of carbon comp resistors gone noisy, as Greco mentioned, but given that its been laying fallow for some time it likely needs some new electrolytic caps as well.
 

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Discussion Starter #9
IMG_2247.JPG thanks for all the great info - turns out there is a fellow recently moved to this area who knows these amps! Gotta love this forum:)
IMG_2247.JPG
 

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Yes, I turned it into a head - I have the original cabinet and speaker still - it never sounded like much - New tubes and 2 Eminence "Cannabis Rex" 12's really woke it up. Its got that nice compression feeling when you play it hard - It probably needs capacitors now - it's quite noisy just sitting at idle...
 

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Discussion Starter #13
This amp has now been repaired by Bill in Penticton (British Columbia) who saw this post and got in touch, Thanks again, Bill. Interestingly, one of the new JJ tubes I had installed was faulty. There were other areas of concern as well, but no capacitors or resistors needing changing. I've used JJ tubes twice now - 1st time was a couple of years back i put their tubes in my vibroverb reissue and it made a world of difference to that amp - in a good way - this time it looks like i got a bad one -
Jim
 
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