Plexi 45 Special Edition

“My tribute to the earliest version JTM45s circa late 1963 into ’64”
-Victor Mason

Vintage Inspiration

The unique tone of the earliest JTM45s comes from features like Radio Spares Power and Output transformers, 6L6 power tubes in the very early days, then the Genelex KT66 power tubes, good preamp tubes (ECC83), quality power rectifier tubes (GZ34), and 2 watt control pots. As a vintage amp collector, Vic had access to multiple examples of early JTM 45 variations, including the early coffin logo variety and a good number of white-faced block logo amps for inspiration and reference. The audio section includes a recording of a vintage JTM45. Listen for the great dynamics and good tone – we based the tone of Plexi 45 Special Edition on this amp and added our modern touches.

Old Stock Tubes

We specified original old stock tubes to equip our Special Edition amps. These tubes are in short supply and we carefully selected, graded, and tested just enough to produce a limited edition of only 16 pieces. Most of these amps are already gone and just a handful remain. Each unit has its serial number engraved on the back panel and that assures the owner that the amp is authentic and we are logging ownership as well. We believe these will be extremely collectible at some point in the future.

Radio Spares OT with Selectable Output Impedance

The chassis is custom built to fit the Radio Spares transformer. The output transformer is specially made for us by Radio Spares to be true to the original. Radio Spares OT’s typically offer only one fixed output impedance, selected at the time of build, due to the complex jumpering needed to set the impedance. But why settle for one impedance and limit options for speaker arrangements? We solved this design challenge by incorporating a unique, expensive switch that enables the Plexi 45SE to select 4, 8 and 16 ohm impedance outputs. You can experiment with different speaker arrangements and cabinets, making the amp that much more flexible.

We also use a very unique platinum metallic silver paint for the faceplates, which are specially made for this edition.

Plexi 45 SE Front

Plexi 45 SE Rear

A Modern Approach to a Classic

While inspired by the past, our Special Edition amp is not a vintage clone. You still get the Mojave essentials like power dampening and line output with ground lift capability that increase the amp’s versatility and usefulness. Our circuit design resolves a number of technical problems associated with early JTM45s that caused destruction of rectifier tubes and other sorts of problems. The Plexi 45 Special Edition represents the refinement and evolution of a classic for today’s musician.

More than just a simple clone, the Plexi 45 Special Edition offers modern essentials built on a classic foundation.

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