Marshall

Marshall 1987 JMP 50-Watt Amplifier (1968)

$5,450.00

Pickup available at 165 Massachusetts Avenue

Usually ready in 1 hour



1968 Marshall 1987 JMP 50-Watt Plexi just into the shop!

What an icon of an amplifier! This is a truly excellent sounding example of one of Marshall's most celebrated amplifiers ever produced. Putting out 50 watts of EL34-powered British tone, it has enough power to rock the biggest stages, but low-volume feel and response that makes it a great club amp.

The amp was recently acquired from a local gentleman and self-proclaimed vintage Marshall fan/collector. It had been slightly modified throughout its life (not the most uncommon practice for many of these amps), but still retained much of its core build, including the original Drake output transformer and choke. The power transformer was replaced some time ago with a similar spec PT, and the circuit was just tidied up by Stan Day.

A toggle switch was added on the front panel decades back, but had been disconnected from the circuit prior to our acquisition. We elected to leave it in place as it presents better than an open hole, in our opinion. A smaller mini toggle switch hole can be seen on the back, once used as some sort of solo/boost switch that was integrated into the circuit. Again, there's no longer evidence of this mod besides the chassis hole. The badge is also a later replacement.

We used this Plexi for a number of electric demos currently available on our YouTube channel, showcasing this amp's versatility. From big, rich cleans to sizzling, throaty saturated overdrive, this Plexi is capable of delivering some of the best British tones of any amp out there.

**Please Note: All vintage amplifiers - regardless of service history - contain electronic components that will eventually require replacement or repair. This is often unpredictable and should be expected as a vintage amplifier owner. We are not responsible for additional service upon receipt.**

Specs

Power
50 Watts
Controls
Presence | Bass | Middle | Treble | Volume I | Volume II
Switches
Standby / Power On/Off
Inputs
Normal Hi/Lo | Bright Hi/Lo

Construction

General
Original cabinet
Covering
Original tolex and handle | Replacement badge

Components

Tubes
(2) EL34 | (3) 12AX7
Transformers
Replacement Power Transformer | Drake 784-139 Output & 352-114 Choke
Service History
Recap / Circuit cleaned up and restored to factory spec by Stan Day | September 2025

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