Marshall 1959 Modified: The Plexi Gets a Master Volume
The Marshall 1959 Modified ($3,699) answers the oldest complaint about the 1959 Super Lead Plexi: it has no master volume. Marshall’s 2025 Modified version adds a master volume, switchable bright cap, and two overdrive modes to the hand-wired, 100-watt EL34 Plexi circuit — all without compromising the legendary tone that made the original the most desired amplifier in rock history. Hand-wired at Bletchley in the traditional Plexi construction style.
Specifications
| Type | Hand-wired all-valve head |
| Wattage | 100W |
| Preamp Tubes | 2 x ECC83, 1 x ECC83 phase splitter |
| Power Tubes | 4 x EL34 |
| Channels | 2 |
| EQ | Treble, Middle, Bass, Presence (shared) |
| Special Features | Master volume, switchable bright cap, two overdrive modes |
| Effects Loop | No (traditional design) |
| Build | Hand-wired in Bletchley, UK |
| Dimensions | 29.2″ W x 11.6″ H x 8.3″ D |
| Weight | 44 lbs |
| Price | $3,699 |
Master Volume on a Plexi: The Modification Everyone Wanted
The original 1959 Super Lead has one fundamental problem: to get the legendary cranked Plexi tone, you need to turn it to ear-splitting volume levels. There’s no master volume in the original circuit — the only volume control is the channel volumes, which also control the gain. The 1959 Modified adds a carefully designed master volume that lets you dial the channel volumes for preamp saturation and then control the overall level separately. This single addition transforms the Plexi from a stage-only monster into a usable professional tool.
Two Overdrive Modes
The two switchable overdrive modes give the 1959 Modified a tonal range the original never had. One mode delivers the classic, smooth Plexi breakup — warm, singing, with that famous sustain. The second mode pushes the preamp harder for a more aggressive, saturated overdrive that approaches high-gain territory. This means one amp can cover everything from early-’70s classic rock to late-’80s hard rock.
Hand-Wired Construction
The 1959 Modified is hand-wired — point-to-point construction using the traditional Plexi building method. This is not a printed circuit board with a Plexi circuit traced on it. Every connection is soldered by hand, every component is individually placed. This construction method contributes to the amp’s feel, responsiveness, and that intangible quality that hand-wired amplifiers possess. At $3,699, you’re getting genuine boutique-level construction from the company that invented this circuit.
No Effects Loop: A Deliberate Choice
Marshall chose not to include an effects loop, keeping the signal path as pure as the original design. Purists will appreciate this decision — nothing in the circuit that doesn’t need to be there. If you need time-based effects, run them in front of the amp or use an external effects loop solution. The 1959 Modified prioritizes tone purity over convenience.
Who Should Buy the 1959 Modified
Players who want the ultimate Plexi experience with practical volume control. Touring professionals who need hand-wired Marshall quality for the road. Collectors and tone enthusiasts who appreciate the finest amplifier Marshall currently produces. Blues-rock and classic rock guitarists who want the most authentic and flexible Plexi available.
FAQ
Is the 1959 Modified worth the price over the Studio Vintage?
They serve different purposes. The Studio Vintage SV20H is a scaled-down 20W Plexi at a more accessible price — great for studios and small venues. The 1959 Modified is a full 100W hand-wired Plexi with master volume and overdrive modes — the ultimate stage amplifier. If you gig on stages where 100 watts matters, the 1959 Modified is the definitive Plexi. For home and studio use, the Studio Vintage delivers 90% of the experience at a fraction of the price.
How does this compare to the JCM 800 Modified?
Different circuits, different character. The 1959 Modified is a Plexi — looser, more open, more dynamic, with a singing quality when pushed. The JCM 800 Modified is tighter, more aggressive, with more preamp gain on tap. The 1959 is the classic rock and blues machine; the JCM800 is the hard rock and metal weapon. Both are 100W UK-built heads — choose based on your tonal preference.
What cabinet pairs best with the 1959 Modified?
The traditional choice is a Marshall 1960 4×12 cabinet with Celestion speakers — Greenbacks for vintage warmth or Vintage 30s for more modern articulation. For smaller stages, a 2×12 cabinet works beautifully and is easier to transport. The 1959 Modified sounds massive through any quality cabinet, but a Greenback-loaded 4×12 is the classic pairing that defined the Plexi sound.
Related Amps & Gear
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- Marshall JCM 800 Modified: 100-Watt British Aggression Upgraded
- Marshall Studio Classic SC20H: JCM800 Power in a Lunchbox
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Frequently Asked Questions
What is the Marshall 1959 Modified?
The 1959 Modified is an updated version of Marshall’s iconic 100-watt Plexi Super Lead. It retains the thunderous clean headroom and harmonic saturation of the original while adding modern features like a master volume and effects loop.
Does the Marshall 1959 Modified have a master volume?
Yes. This is one of the key modifications — the addition of a master volume lets you access the amp’s legendary cranked Plexi tone without the ear-splitting volume levels the original demanded.
What’s the difference between the 1959 Modified and the original 1959SLP?
The Modified version adds a master volume control, an effects loop, and updated components for improved reliability, while preserving the original’s circuit topology and tonal character. It’s the Plexi many players always wished Marshall would make.