79 JMP 2203

[rickenbacker198]

Picked up this amp today,

I’ve been waiting for a few months for a decent deal on a JMP2203 and this one finally popped up.
Made the same year as me too!

I haven’t had a chance yet to crank it right up.
It sounds absolutely fabulous at low to mid volumes. Seems to take drive/ fuzz pedals extremely well through the low input.
It’s been years since I’ve had a real Marshall and this one seems to deliver.

At some time someone added an extra preamp socket but it was never soldered.

Can I ask you Marshall experts,

Does it look stock to you??

There is what looks to me an extra wire (thin black) running to the first preamp tube from the preamp pot.

Would you be worried by the rust on the transformers? Should I clean them up and coat them in something ?

Anyone know the brand of the preamp tubes ?
Are these Ei?

Appreciated

 

[Chubbs]

The blue metal oxides (not sure if they are stock values), sozo caps (2), screen resistors, cap going to the gain pot, and cap going to the presence pot don’t look stock but that’s nothing I’d be concerned about. Might want to switch out the plate and grid metal oxides on v1 if your a purist. Bias caps and filter caps aren’t original either but the stock ones suck anyway.
The thin wire on v1 looks to not be stock but serve’s the correct purpose. Transformers look fine to me provided they don’t have any internal issues.

 

[SpiderWars]

Cool amp! @Chubbs covered just about everything I saw. Somebody's been in there but it looks relatively "back to stock". I think those blue resistors are actually metal film and I would leave them. And you have a spare preamp tube holder! I actually thought about doing that to one of my Marshall builds since the chassis already had the hole and I needed to fill it with something.

 

[1984_5150]

https://www.mercurymagnetics.com/transformer-rust-friend-or-foe/

 

[panhead]

https://www.mercurymagnetics.com/transformer-rust-friend-or-foe/

Sounds like something a TGP member would do.

 

[GlideOn]

No it does not look stock.

However, it looks extremely clean and wouldn't be terribly hard to make use of that extra preamp slot for an added gain stage to make it a genuine high gain amp, capable of knocking the socks off of most modern amps. These are extremely easy amps to work on.

 

[Chubbs]

If your handy with a soldering iron I’d put in a new wire on v1 since the one there looks undersized, maybe new screens too just for peace of mind. Maybe wire up a fourth preamp tube too…