The JCM800 series (Model 2210 and others) is a line of guitar amplifiers made by Marshall Amplification. First built in 1975 (Models 2203a and 2204a), the JCM800 became a staple of 1980s hard rock music; notable users include "Slayer, Anthrax, Judas Priest, Iron Maiden, and about any other '80s hard rock/metal band".
In 1981, Marshall finally reached the end of its 15-year distribution deal with Rose-Morris, which had severely limited its potential to sell amplifiers outside of England; Rose-Morris tagged 55% onto the sticker price for exported models. The JCM800 was the first series produced after the contract expired. The name comes from Jim Marshall's initials, "J.C.M.", coupled with the meaningless "800" from the number plate on his car. It was later noted that "800" stood for the decade. For example, the JCM900 was released in 1990 and the JCM2000 was released in 2000.
The series included head amplifiers with matching cabinets, as well as combos, and was produced until the 1990s. It quickly became a very successful amplifier, and ubiquitous among hard rock and heavy metal bands.
These were the second series of Marshalls equipped with a master volume, which allowed for more distortion at lower volumes. Compared to the earlier "Master Volume" series, they offered some advantages, including the possibility to be patched internally and linked with other amplifiers. The first JCM800s were in fact Master Volume amplifiers (Models 2203 and 2204, at 100 and 50 watts respectively), repackaged in new boxes with new panels. Soon, however, the Model 2210 appeared on the market. These were equipped with two channels, which could be activated via a foot switch, allowing for separate lead and rhythm sounds. They also had an effects loop and reverb, also a first for Marshall.
Initially, users complained that the amplifiers (used with the standard Marshall cabinets) sounded flat compared to the older Marshalls, until it was discovered (by accident) that the fault was with the speakers: The new cabs had been equipped with a new kind of Celestion speakers. Marshall quickly reverted to the older Celestions. Still, some users prefer the pre-JCM800 amplifiers, claiming that those have a warmer, less "brittle" sound.
The amplifier was equipped with EL34 valves (tubes) for amps sold in the UK and 6550 tubes for amps exported to the United States. The JCM800 is considered a "hot" amplifier because it has more gain stages than comparable amplifiers, and in "lead" mode (in the "high" input), an extra triode provides extra gain to the pre-amplifier, which "made for one hot rock amp".
- Jeff Beck
- Dino Cazares
- Billy Corgan
- Bradley Nowell
- Steve Cradock
- Brett Gurewitz
- Buddy Guy
- Jeff Hanneman
- James Iha
- Bill Kelliher 
- Kerry King
- Tom Morello
- Mike Mushok
- Mick Ralphs
- Elliott Randall
- Brian Tatler
- Leslie West
- Zakk Wylde
- Lee Malia
- Kevin Shields
- Angus Young
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- "Gitarist Gearchat: Mastodon's Bill Kelliher".
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