It has been confirmed that EVH plexi was stock by many people like Suhr, Friedman and even George metropoulos.
So people began to think that evh had a regular 68' 12000 series and the story ends there. However as you may know about vintage gear, it hapenned that sometimes the guys at marshall's were short on components and used other parts resulting in variations in amplifiers and in tone. this is what supposedely happened to EVH plexi.
Even if EVH plexi is stock, many values have nothing to do with a stock plexi of the 12000 series. Here is a board values of the EVH plexi (in the yellow rectangle) according to pictures of the Suhr Sl68. The major differences with a regular 12000 series have been circled in yellow.
This is the "regular" (there had some variations of it) version of the 12000 series :
The principal mod that was done to this plexi was the replacement of the middle pot by a 50k mid pot instead of the regular 25k : this was confirmed by george metropoulos and Friedman.
Now for the 5000 pf bright cap it is supposed that it was used as some models of sl68 have it and others don't.
the last mod was the use of (sylvania) 6ca7 fat bottle tubes a variation of the el34.
Dave friedman recieved eddies plexi to repair the transformer. He found a stock plexi with the same transformer and rewound the wire on the original one. here is what Dave friedman apparently said in metropoulos forums about eddies plexi :
Post by RACKSYSTEMS » Wed Feb 02, 2011 11:40 pm
Split cathode V1a 250uF/820,V1b .68/820
All coupling caps are 0.022uF,Bright channel coupling cap is 0.0022uF
470k mixer resistors
500pf [red out of 69 amp] mixer bypass cap
Bypass cap on V2a is .68uF and a 220uf to 470uf
33k/560pF lemco tone stack combo
100k NFB resistor at 4 ohm tap
220k bias splitter resistors
0.1 uF cap on presence control
.022uf output couplers
filtering is
2] 100uf's f&t in series mains
2] 32uf's f&t in series screens
1]100uf lcr phase inverter
1] dual 33 x 33 f&t preamp
It is interesting to see how variations of components even in a stock plexi could change the tone of an amplifier. Little accidents like shortage of components made those variations happen sometimes in the past. What is more funny it is that one of these ended up in the hands of a great guitar player. Just imagine the probabilites of it happening... crazy !
EDIT : Now there is still a possibility that eddie plexi had jose arredondo mods and that they influenced his signature tone and that those mods were removed when the amp went to the technicians. Yeah eddie knew a lot about gear. Steve Vai and Pete thorn seem to allude that perhaps josé had something to do with eddies plexi in this video :
Why am i posting this here ? To share but there is also a hope that Marshall will begin to do what prs did with hendrix and their HDRX 20. Recreating the tone of an icon of rock and making it available in a small size box. They reversed engeneer the transformers and made a 20watt version of it to miniaturize the tone. Finally they added a master volume on a plexi !!!
Now let's imagine that marshall made a 20 watt plexi called the SL78 (reference to evh first album) with those values above, a 50k mid pot, a PPIMV master volume, fx loop and finally they reduced the size compared to the sv20... Well they would sell many...
So people began to think that evh had a regular 68' 12000 series and the story ends there. However as you may know about vintage gear, it hapenned that sometimes the guys at marshall's were short on components and used other parts resulting in variations in amplifiers and in tone. this is what supposedely happened to EVH plexi.
Even if EVH plexi is stock, many values have nothing to do with a stock plexi of the 12000 series. Here is a board values of the EVH plexi (in the yellow rectangle) according to pictures of the Suhr Sl68. The major differences with a regular 12000 series have been circled in yellow.
This is the "regular" (there had some variations of it) version of the 12000 series :
The principal mod that was done to this plexi was the replacement of the middle pot by a 50k mid pot instead of the regular 25k : this was confirmed by george metropoulos and Friedman.
Now for the 5000 pf bright cap it is supposed that it was used as some models of sl68 have it and others don't.
the last mod was the use of (sylvania) 6ca7 fat bottle tubes a variation of the el34.
Dave friedman recieved eddies plexi to repair the transformer. He found a stock plexi with the same transformer and rewound the wire on the original one. here is what Dave friedman apparently said in metropoulos forums about eddies plexi :
Post by RACKSYSTEMS » Wed Feb 02, 2011 11:40 pm
Split cathode V1a 250uF/820,V1b .68/820
All coupling caps are 0.022uF,Bright channel coupling cap is 0.0022uF
470k mixer resistors
500pf [red out of 69 amp] mixer bypass cap
Bypass cap on V2a is .68uF and a 220uf to 470uf
33k/560pF lemco tone stack combo
100k NFB resistor at 4 ohm tap
220k bias splitter resistors
0.1 uF cap on presence control
.022uf output couplers
filtering is
2] 100uf's f&t in series mains
2] 32uf's f&t in series screens
1]100uf lcr phase inverter
1] dual 33 x 33 f&t preamp
It is interesting to see how variations of components even in a stock plexi could change the tone of an amplifier. Little accidents like shortage of components made those variations happen sometimes in the past. What is more funny it is that one of these ended up in the hands of a great guitar player. Just imagine the probabilites of it happening... crazy !
EDIT : Now there is still a possibility that eddie plexi had jose arredondo mods and that they influenced his signature tone and that those mods were removed when the amp went to the technicians. Yeah eddie knew a lot about gear. Steve Vai and Pete thorn seem to allude that perhaps josé had something to do with eddies plexi in this video :
Why am i posting this here ? To share but there is also a hope that Marshall will begin to do what prs did with hendrix and their HDRX 20. Recreating the tone of an icon of rock and making it available in a small size box. They reversed engeneer the transformers and made a 20watt version of it to miniaturize the tone. Finally they added a master volume on a plexi !!!
Now let's imagine that marshall made a 20 watt plexi called the SL78 (reference to evh first album) with those values above, a 50k mid pot, a PPIMV master volume, fx loop and finally they reduced the size compared to the sv20... Well they would sell many...
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