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This was the amp Eric Clapton used on the legendary John Mayall's Bluesbreakers "Beano" album early in 1966. These amps didn't sound quite as good as the original 18W amps though. In 1967 the JMP (Jim Marshall Products) panels were introduced. The 50W models featured 8 inputs & 4 channels instead of the usual 4 inputs & 2 channels. User manual for Master Volume and Lead models: 1959, 1987, 2203, 2204, 4001, 4010, 4103, 4104, 5002, 5005 & 5010 (483k B). User manual for Master Volume and Lead models: 1959, 1987, 2203, 2204, 4001, 4010, 4103, 4104, 5002, 5005 & 5010 (483k B). User manual for Master Volume and Lead models: 1959, 1987, 2203, 2204, 4001, 4010, 4103, 4104, 5002, 5005 & 5010 (483k B).Very few of the 1972 2x12" (horizontal) extension cabinets were built and these cabinets are very rare. These G12-20 speakers were 'M' magnet speakers with an H1777 cone. These amps used two EL84 tubes in the power amp, two ECC83's in the pre amp and a solid state rectifier in the power supply. This set consisted of a 20W head amp and two speaker cabinets each with fitted two 13"x8" eliptical speakers. In July 1969 Marshall dropped the Plexi face plates and switched to the gold colored brushed aluminium metal face plates as we know them still today. It features a high treble channel and a normal channel. The 100W models were built with 4 inputs & 4 channels. This amp was in production from early 1972 up to late 1973. It is pretty rare as it was only available through mailorder. JCM800 pre amp schematic with 3x ECC83 for models: 1959, 1987, 2203, 2204, 2103 & 2104 .The speaker cabinets were closed 4x12" Celestion loaded cabinets. It isn't clear if these amps were actually part of the JCM800 series.The first combo's (models 1961 & 1962) appeared halfway this year. The schematics suggest they are, but you won't find JCM800 printed on the amps.Desperate to build a factory large enough to meet demand, Jim Marshall made a deal with the Rose Morris company. (Thanks to Christos) This amp was in production from 1976 up to 1980. It was fitted with two Celestion G12L T1632 8Ω speakers. Special high power version of the speaker cabinets were made for these beasts. This was the accompanying cabinet for the 2001 Bass amp.In exchange for the necessary funding (to build this new factory) Rose Morris acquired the exclusive worldwide rights to distribute Marshall amps for the next 15 years. See the Marshall Amps 2000 page for more "official" information on the 2000 amps.The mix resistors (which mix together both channels after the first triode sections) were originally 270kΩ on the early models. In the first half of 1967 the JTM panels were dropped all together and the JMP panels were introduced. A tube rectifier was just too much hassle and too expensive. In 1965 Marshall introduced the 18W "practice" combo amps. These amps used two EL84 tubes in the power amp, three ECC83's in the pre amp and an EZ81 rectifier in the power supply. It was fitted with a reverb and a 6d B Boost foot switch. These 4140's were first fitted with two Mc Kenzie 12" 80W speakers. It was one of the first all transistor Marshall heads. This was the head version of the 2200 Master Lead Combo. Under the JCM800 "regime", the model numbering was changed.
Keep in mind that allthough I try to be complete, this is obviously not a complete list, though I hope it will be some day... The circuit was a 1959 Fender Tweed Bassman (circuit 5F6-A) clone. In the first half of 1967 the JTM panels were dropped all together and the JMP panels were introduced. In the top left corner of the cabinet a '100W' logo could be seen. In the course of 1968 the Low-High tone control circuitry was changed to a Low-Mid-High tone control and these amps were now called the Marshall Majors. The JCM800 range is split into the Lead amps (this section) the Bass amps and the solid state amps. The (Super) Leads (1959 & 1987) were issued as heads only, while the Master Volumes (2203 & 2204) and the new Split Channels (2205 & 2210) were also issued as combo's (4103, 4104, 4210, 4211 & 4212).
The very first (prototype) Marshall amps were built in 1962 in Jim's kitchen. It is said that the first prototype and early production amps were fitted with two 5881 beam power tetrodes, three ECC83's and a GZ34 rectifier tube, but soon KT66 tubes were used instead of the 5881's. See the Plexi Palace JTM45 page for some great JTM45 pictures. To reflect this the JTM45 panels were changed to JTM50 panels. The early incarnations of the JTM100's varied in design. Using four KT88 power tubes, these amps were very powerfull, very loud and very expensive. An ECC82 was used as the driver tube for the four KT88's. the "Pig" from 1967 (thanx to and courtesy of Jacques of Generic 200W Amp schematic with 2x ECC83, 1x ECC82 & 4x KT88 . The JCM800 amps had a larger logo than before, and the heads also featured grille cloth on the upper two thirds of the front instead of being completely covered with the usual black vinyl.
In these early years the amps, their features and especially the cosmetics varied a lot. The Fender Bassman used a 12AY7 as the input tube but the JTM45 was fitted with a 12AX7/ECC83 which has a higher gain. The GZ34 rectifiers were phased during this time, allthough there are even JMP 50 models with GZ34 rectifiers. The JTM100's were the first amps to use solid state rectifiers. See the Marshall Arts Major page for more information on these Marshall Majors. The Club and Country were introduced in april 1978 and were discontinued in 1982. In 1982, the 20th anniversary of Marshall Amps, some of the JCM800 amps were issued in neat white vinyl.
Too many Marshalls were coming back under warranty with defective output tubes. It was discontinued in 1980 just prior to the introduction of the JCM800 range. It uses an ECL86 tube as the reverb driver/recovery tube. User manual for Master Volume and Lead models: 1959, 1987, 2203, 2204, 4001, 4010, 4103, 4104, 5002, 5005 & 5010 (483k B).
Apparently the EL34's didn't like to be knocked about while being shipped from Europe to the US of A. JCM800 pre amp schematic with 3x ECC83 for models: 1959, 1987, 2203, 2204, 2103 & 2104 .