Marshall JTM Model 1968 Super PA 100 Plexi Model Tube Amplifier (1967), made in London, England, serial # SP/20204, black tolex covering finish.
Marshall amps are certainly a rock legend, with a sound that has defined both an entire style and era of music. This Plexi 100 watt Super PA head is a real monster, both in volume and tone. All Marshall amps owe their humble beginnings to the Fender Bassman 5F6-A, re-interpreted using English components and originally sold exclusively through Jim Marshall's Hanwell, London shop. Both the circuit design and sound soon evolved from the Fender paradigm into something entirely their own.
Early Marshalls powered the sound of the Who, Cream, Hendrix and beyond, de rigeur among top UK groups by 1968-9. Although the dedicated bass models were popular with many A-list bassists (arguably more so than the original Bassman) many notable guitarists have also chosen the Super Bass model over the Super Lead; Jimi Hendrix, Jimmy Page, and Eric Johnson, to name a few. The Super PA on the other hand, has gathered a strong following in more recent years, used perhaps most notably by J. Mascis of Dinosaur Jr.
By 1966 Marshall had become very involved in PA equipment, and their distributor Rose-Morris wasn't particularly interested in the large guitar amps (perhaps they were related to Dick Rowe at Decca who turned down the Beatles!). The Super PA was the only model listed in the initial price sheets and catalogs, at the grand price of 95 pounds. The Super Lead and Super Bass didn't get proper marketing until the '67 catalog, by which point those amps were already legendary. No wonder why the bulk of the first amps were sold exclusively through Jim's shop in London!
Electronically, the Super PA, Super Lead and Super Bass models were nearly identical, save for a few minor preamp voicing components, making it easy to modify one circuit into the other. Where the Super PA differs the most perhaps is it's daunting 8 input array; four channels with two inputs each. Because of this, the PA models are a tad quieter/cleaner at the input stage than their Lead and Bass siblings at the same settings, making them excellent for use with pedals. And if breakup is desired, up to four channels can be jumpered for inordinate amounts of gain!
Besides the 8 inputs, this Plexi head has the same treble, middle, bass and presence controls and a separate volume control for each of the four channels. Like the other "Super" models, the head sports a quad of EL34 power tubes, putting out a whopping 100-watts, typically into a "full stack" of two of Marshall's iconic 4x12" closed-back Celestion G-12-laden cabinets.
These amps came of age in the late 1960s, an era when bands routinely played large stadiums and festivals, often without PA sound reinforcement for the guitars. In 1969 amplifiers with this sort of power were a necessity rather than a luxury, and the tone became the new rock standard. These days, we have the luxury of attenuators, to tame these beasts somewhat and protect our ears from their unbridled fury!
Height is 11 in. (27.9 cm.), 29 in. (73.7 cm.) width, and 8 in. (20.3 cm.) in depth at deepest point.
Cosmetically, this Plexi head has clearly seen some use but remains in really well-preserved condition for its age. The black Tolex covering shows some scuffing, most notably around the corners. Both the original handle and the gold piping on the head remain in great condition for their age. The Plexi-glass front panel is in great condition showing very little wear overall with only one notable spot of typical hazing around the power and standby switches. The original knobs are all nicely intact, free of cracking and none are missing! The original "gold on cream" logo is intact, though with quite a bit of the gold coloring worn off.
Electrically, this amp is nicely original. The amp's power, choke and output transformers all appear to be original and are coded 1203-80, 552-114 and 1202-119 respectively. All pots retain undisturbed solder joints throughout and all appear original to the amp as well. The amp has otherwise seen our typical maintenance and servicing, including replacement of all electrolytic capacitors, install of a new grounded 3-prong power cord, all sockets, pots and jacks cleaned and power section biased to spec with a new matched quad of the robust and ever-reliable JJ EL34 power tube. The amp is set up for US voltage and as they used to say, "Ready To Rock". Overall Excellent - Condition.
