Post Your Plexi

LeftyLoungeLizard

LeftyLoungeLizard

Roadie
TGF Recording Artist
Messages
314
Modern, kit or original!

Mine started out as a JTM45 Reissue from 1996 (paid $600 to a guy on Plexi Palace forum in '03).

Problem is/was, the reissue circuit is more "loosely based on JTM45" than accurate (like many of the earlier reissues were).

In 2003, I modded it via Lord Valve's instructions to a true '66 with PTP, correct values, VA KT66s, Mallorys and Merc Mags OT etc

In 2013, I changed a few values to make it more 1987 circuit

In 2017, in the quest for "MOAR GAINZ", I went through the whole thing and turned it into a '68 Plexi
(Ed 12301 spec) with .68uF bypass on V2... kept the tube rectifier.

Mojotone 50W Heyboer OT. Sozo New Edition (or whatever they were called) caps.





PB190690-768.jpg


Installing the Mojotone Heyboer OT

fetch.jpg
 
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Awesome journey!

I have a JTM 50 built on a Ceriatone board with the same caps you have and Merren OT. Ear splitting. I have it modded to be switchable to various Marshall specs. I didn't add a master and I regret it haha, Thanks to the Power Station for making it useful.
 
Mine is from 2023 (MAV transformers) 1987x converted to 1969 spec.
V1B: 2.7k+0.68u, Coupling: 0.0022u, V2A: 820+0.68u,

It's my first experience with a real NMV amps, it took me several days to understand the amp and learn how to control and play it.

20240114_145905.jpg






EOengineer said:
A post phase inverter master is IMO table stakes at this point. It’s hard to use a 4 holer without it in today’s low volume hellscape. :rofl
Click to expand...
100%
I tried to turn the Treble channel past 0.1 into my cab, I believe I may have damaged something, don't know what yet, but it was definitely damaged.
edit: I'm joking of course, it is f'ing LOUD, unusable anywhere without a PPIMV or an attenuator/load box.
 
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I built a 50W amp that switches between circuits, from a 1986 to 1989 to some mash of different 1987 specs. No Plexi cosmetics at all, maybe not fully accurate circuit, but still wanted to share.

It’s a mutt in terms of parts: Classictone transformers, some components from Valvestorm, some from Mouser, metal film resistors instead of carbon comp or carbon film, 3 way bright caps on both channels, too many things to list.

Sometimes I wish I built a straight up kit, but sometimes I appreciate this Frankenstein.



I’ve shared this captures of this amp to the NAM community before.

https://tonehunt.org/OutmodedElectronics/14967784-9d49-45da-8baf-c6d54980d7a9

I’ve been able to dial in Helix’s Brit Trem Brt and Voltage models to sound a bit like my amp.
 
James Freeman said:
Mine is from 2023 (MAV transformers) 1987x converted to 1969 spec.
V1B: 2.7k+0.68u, Coupling: 0.0022u, V2A: 820+0.68u,

It's my first experience with a real NMV amps, it took me several days to understand the amp and learn how to control and play it.

View attachment 18294






100%
I tried to turn the Treble channel past 0.1 into my cab, I believe I may have damaged something, don't know what yet, but it was definitely damaged.
edit: I'm joking of course, it is f'ing LOUD, unusable anywhere without a PPIMV or an attenuator/load box.
Click to expand...


So describe the tonal difference between stock and '69 (granted, Marshall improved their re-issues but still).

Yeah that .68uF on V2 ups the gain nicely. Historically from what I've heard, Marshall didn't put that .68uF on many plexis (and it was only the plexi era) back in the day stock, only some. So if you luckily got one with the bypass in the late 60s, 70s, 80s etc you had the bee's knees.
 
bikescene said:
I built a 50W amp that switches between circuits, from a 1986 to 1989 to some mash of different 1987 specs. No Plexi cosmetics at all, maybe not fully accurate circuit, but still wanted to share.

It’s a mutt in terms of parts: Classictone transformers, some components from Valvestorm, some from Mouser, metal film resistors instead of carbon comp or carbon film, 3 way bright caps on both channels, too many things to list.

Sometimes I wish I built a straight up kit, but sometimes I appreciate this Frankenstein.



I’ve shared this captures of this amp to the NAM community before.

https://tonehunt.org/OutmodedElectronics/14967784-9d49-45da-8baf-c6d54980d7a9

I’ve been able to dial in Helix’s Brit Trem Brt and Voltage models to sound a bit like my amp.
Click to expand...

Sounds great. Yeah NAM is cool; had it awhile and it really works! More people need to check it out.
 
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IMG_9847.jpeg



1969 Super Lead 100. Not all original. Eric Johnson owned it around 2009, then sold it to his tech. I have gut shots somewhere.

When I got it the bias was all the way up so it must’ve been variac’d. Sounds glorious

Cab is a 1972 1960A. Speakers are Weber 1225 w/ pre rola doping
 
AutomationBias said:
I had one of these (bought it new in 1996)! I stupidly sold a JCM 800 to buy it because it looked like 'a real plexi' and was sorely disappointed.
Click to expand...

Yeah those early reissues were mostly a joke tone wise. Fooled everyone with their looks. I also had a minty 1959S 100 watter (the 1959S and 1987S were Marshall's very first reissues in 1988-89) that sounded decent but the look was an amalgamation of leftover head shells, logo and shit. They were obviously trying to get rid of old stock parts.
 
LeftyLoungeLizard said:
Yeah those early reissues were mostly a joke tone wise. Fooled everyone with their looks. I also had a minty 1959S 100 watter (the 1959S and 1987S were Marshall's very first reissues in 1988-89) that sounded decent but the look was an amalgamation of leftover head shells, logo and shit. They were obviously trying to get rid of old stock parts.
Click to expand...
The worst of it was that my JCM800 was a 1987x circuit, and probably the best amp I've ever owned. I got completely sucked in by the aesthetics.
 
James Freeman said:
Mine is from 2023 (MAV transformers) 1987x converted to 1969 spec.
V1B: 2.7k+0.68u, Coupling: 0.0022u, V2A: 820+0.68u,

It's my first experience with a real NMV amps, it took me several days to understand the amp and learn how to control and play it.

View attachment 18294






100%
I tried to turn the Treble channel past 0.1 into my cab, I believe I may have damaged something, don't know what yet, but it was definitely damaged.
edit: I'm joking of course, it is f'ing LOUD, unusable anywhere without a PPIMV or an attenuator/load box.
Click to expand...

That sounds KILLER dude!!!
The musical artifacts all around the notes is so rad!!
 
James Freeman said:
Mine is from 2023 (MAV transformers) 1987x converted to 1969 spec.
V1B: 2.7k+0.68u, Coupling: 0.0022u, V2A: 820+0.68u,

It's my first experience with a real NMV amps, it took me several days to understand the amp and learn how to control and play it.

View attachment 18294






100%
I tried to turn the Treble channel past 0.1 into my cab, I believe I may have damaged something, don't know what yet, but it was definitely damaged.
edit: I'm joking of course, it is f'ing LOUD, unusable anywhere without a PPIMV or an attenuator/load box.
Click to expand...

James, what speakers are used in this clip ?

Are you variac'ing it down ?
 
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bikescene said:
I built a 50W amp that switches between circuits, from a 1986 to 1989 to some mash of different 1987 specs. No Plexi cosmetics at all, maybe not fully accurate circuit, but still wanted to share.

It’s a mutt in terms of parts: Classictone transformers, some components from Valvestorm, some from Mouser, metal film resistors instead of carbon comp or carbon film, 3 way bright caps on both channels, too many things to list.

Sometimes I wish I built a straight up kit, but sometimes I appreciate this Frankenstein.



I’ve shared this captures of this amp to the NAM community before.

https://tonehunt.org/OutmodedElectronics/14967784-9d49-45da-8baf-c6d54980d7a9

I’ve been able to dial in Helix’s Brit Trem Brt and Voltage models to sound a bit like my amp.
Click to expand...

I think I’ve tried your NAM captures and they sounded good.

NAM is so killer!
 
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