JC-120 in need of a lot of love

[laurie]

Picked up this amp the other day for USD$110.

It is exactly as you see it. Apparently the chorus channel still works through the Yamaha speaker. Good news is that the MN3002 is physically present. No idea if it works.

LOTS of TLC needed on this one to bring it back to life. It will likely be a multi-year project while I wait for time/parts. But the price was right and if I can rescue it that will be an excellent thing - a 40 year old amp back to life.

• One of the channel circuit boards was out of the amp in a bag, failed with burned components. The knobs and mounting hardware were, fortunately, in the bag.

• The other channel was still in the amp and apparently worked - I wasn't able to try it before I bought it.

• Both original speakers were missing, and the cabinet came with a Yamaha speaker loaded in one side only.

• The cabinet has been used as a plant-stand or been stored outdoors for years. The amp chassis was full of leaves and debris.

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[laurie]

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[The_Doc]

Good luck with this one Laurie and I hope you can save it, however long it takes.

Just watch your lower back - these are so heavy ! I guess they come with wheels for a reason

The JC range of amps are some of the best I’ve played through for clean stereo sounds. I can’t get enough of them.

[Pepe]

Wow! Even for spare parts this is a good price. Has a rectifier (or some other sort of transistor) died and burned in the first picture? This is not dirt, or is it?

[laurie]

Wow! Even for spare parts this is a good price. Has a rectifier (or some other sort of transistor) died and burned in the first picture? This is not dirt, or is it?

Burned components. Resistors, at least. Not sure yet what else.

Power transistors have been removed from the chassis. Not sure why. We shall see...

I can post what I find as I (slowly) go through the repair process in this thread if anyone is interested?

[Pepe]

if anyone is interested?

What a question!

[laurie]

Good luck with this one Laurie and I hope you can save it, however long it takes.

Just watch your lower back - these are so heavy ! I guess they come with wheels for a reason

The JC range of amps are some of the best I’ve played through for clean stereo sounds. I can’t get enough of them.

I've owned one of these before, and yeah, I can relate!

Fortunately(!) this one only has one speaker so far, so not too bad. I have no idea what to do for replacement speakers. I'm thinking maybe 12" JBL PA drivers (I have a couple in deep storage in Australia I could have sent).

[laurie]

if anyone is interested?

What a question!

OK OK. Will post.

[laurie]

This MIGHT be less painful than I thought.

Picked these up yesterday at the local thrift store for USD$45 for the pair. From the right period. Theoretically the 12" drivers are "flat-ish", "full-range-ish".

No idea how they will sound in the JC-120, but for the price I can always flip them if they are not good.
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[laurie]

https://www.sammisound.com/en/product/p ... rder%3AASC