Help with L120, How Original?

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Help with L120, How Original?

Postby sound city 69 on Thu May 12, 2016 9:39 pm

I may buy this head but am concerned about what looks like a mod. There is a strange looking greenish box mounted on the rear of the chassis behind the serial number badge. Any ideas as to what it is?
It has a fan added as well, I mention the fan incase the box has to do with the fan. Any other mods you see? Thanks for your help.

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Re: Help with L120, How Original?

Postby Papa Dog on Fri May 13, 2016 12:13 pm

hard to see exactly what is going on there
but that could be my monitor or my eyes (having some issues again)
That "can" looks to be a honking big capacitor. Could be that a proper power supply unit could not be sourced what that was added, or else it is additional filtering, for whatever reason.
The fan could be removed, and the only issue will be cosmetic.

Are those 6l6 or 6550 power tubes? They should be El34s, but are not, and look to be 6550s. They can be made to work, and might have been "what was available" "back in the day", but the amp will never sound "correct".

"sensitivity switch" has been replaced, but I would pull it in favor of a 22k 1 watt pot anyway. There should be some crappy board mounted trimmers in that circuit, and I like a little more "granular" control. Not a substitute for a master volume, but it controls the volume and bias on that tube.

Yeah, if you can get it for a reasonable price. It might "work" but it has been hacked and modded, at least some. And it looks to me that it was "fixed" with available parts and never put to rights once the internet (and thus proper parts) came along. Oh, yeah...if it has been THAT long it is likely to need a full cap job as well.
Ohm yeah, it will require a proper 3 wire power cable, removal of the "grounding switch (or at least unhook it) and "death cap".
For the right money it would be an interesting resto/project.
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Re: Help with L120, How Original?

Postby sound city 69 on Fri May 13, 2016 4:45 pm

Thanks P.D.,

The price is right but I don't need any more projects now, and I'm not an amp tech so I'll probably pass on this one.
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Re: Help with L120, How Original?

Postby Papa Dog on Fri May 13, 2016 5:51 pm

sound city 69 wrote:Thanks P.D.,

The price is right but I don't need any more projects now, and I'm not an amp tech so I'll probably pass on this one.


No problem, you're welcome.
Sorry the news was not better.
There Ain't No Such Thing As A Free Lunch.

"The time has come," the Walrus said,
"To talk of many things:
Of shoes--and ships--and sealing-wax--
Of cabbages--and kings--"
Papa Dog
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Posts: 1337
Joined: Mon Mar 15, 2010 6:48 pm
Location: Narly Ampwerks


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