Plexi VS JMP designs

walters

New member
Whats the difference between a PLEXI VS JMP?

The preamp section, cathode follower circuit, tone stack, output stage looks the same to me

Is the plexi output transformer different than a JMP transformer how and why?

what else is a big difference between the two designs?
 
Re: Plexi VS JMP designs

The JMP was one of teh first to have a master volume. Aside from that, wait for one of the amp experts to come along regarding circuit design differences, etc.
 
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Re: Plexi VS JMP designs

GJ - which of the schematics shown on either of these two pages is the "Plexi" by your definition?
Marshall Schematic Heaven
Hoffman Schematics

Also, which "JMP" are you referring to? They go all the way from the "1959 Lead 50 Watt" to the "2204" (which has a totally different architecture)?

Or are you just jerking our collective chains with the idiot (savant?) personality again?

Chip

P.S. Please accept my apologies for the last question "Walters" if you are a "real" person and not a personna.
 
Re: Plexi VS JMP designs

Special electrolytic caps from Bulgaria, handcrafted by 72 virgins.
 
Re: Plexi VS JMP designs

Special electrolytic caps from Bulgaria, handcrafted by 72 virgins.

I've heard that those caps were made of either lead azide or potassium perchlorate? The substance was hammer forged by each of the virgins into the typical cap shape we all know and love before they jammed leads into each end and covered them with paper rolls. The precise barrel shape and chemical composition determined the value of the cap.

:usa2:
 
Re: Plexi VS JMP designs

I've heard that those caps were made of either lead azide or potassium perchlorate? The substance was hammer forged by each of the virgins into the typical cap shape we all know and love before they jammed leads into each end and covered them with paper rolls. The precise barrel shape and chemical composition determined the value of the cap.

:usa2:

Wow, sounds dangerous.

All lawyers to Bulgaria! :yell:
 
Re: Plexi VS JMP designs

Wow, sounds dangerous.

All lawyers to Bulgaria! :yell:

...via Slavery-Class Air freight. The in-flight meal will be Fry Babies on toast, and for your viewing pleasure, Maximum Giraffe Rape starring Lou Diamond Phillips.
 
Re: Plexi VS JMP designs

GJ - which of the schematics shown on either of these two pages is the "Plexi" by your definition?
Marshall Schematic Heaven
Hoffman Schematics
































































I dunno. :bigok:

Retard.jpg

:laughing::laughing::laughing:
 
Re: Plexi VS JMP designs

"1959 Lead 50 Watt" to the "2204" (which has a totally different architecture

what are the circuit design differences between a Plexi VS a 1959 JMP?
 
Re: Plexi VS JMP designs

The 1959 circuit didn't change that much over the years and from 1968-1969 you could get a 1959 'plexi' that said 'JMP' on the front panel. If you're asking the difference between the late 60s 1959 and the later 1970s model, the 70s version is brighter and slightly gainier. I know the negative feedback was reduced, but I don't know if other circuit changes were made.
 
Re: Plexi VS JMP designs

"1959 Lead 50 Watt" to the "2204" (which has a totally different architecture

what are the circuit design differences between a Plexi VS a 1959 JMP?

They changed the circuit from a plexiglass face to a metal face.
 
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