[1] It quickly became a very successful amplifier, and ubiquitous amongst hard rock and heavy metal bands.
Compared to the earlier "Master Volume" series, they offered some advantages, including the possibility to be patched internally and linked with other amplifiers.
[3] 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.
[4] These were equipped with two channels, which could be activated via a foot switch, allowing for separate lead and rhythm sounds.
[3] The amplifier was equipped with EL34 valves (tubes) for amps sold in the UK, Europe, and Canada.