Marshall amplifiers have been popular with rock-and-roll musicians since at least the mid-60s. There are a few main reasons for this. Marshall Amplification was founded in Britain by a man named Jim Marshall. While his early model Marshall amps were similar to other name-brand products of the era, Jim Marshall would soon create a distinguished style of amplifier that has yet to be surpassed. Marshall amps continued to evolve in the 60s, ultimately putting their own stamp on amplification systems and rock and roll in general. Rock and roll's demand for ever louder amplification led Marshall to come out with a beefed up 100 watt amplifier. This model of Marshall amps was ultimately made famous by the likes of Jimi Hendrix and Eric Clapton.
The Marshall Stack has a preferred position in the halls of rock and roll as one of the loudest, best-sounding amplification systems available. These are multi-unit systems that consist of an amplifier and two large speaker cabinets, each containing four 12-inch speakers. The smaller amplifier can be "stacked" on the speakers and then connected by means of an audio cord. This makes the stack both easier to transport and simpler to modify for various staging purposes.
Due to the huge popularity of the full Marshall Stack, there are a number of different variations on the stack theme. You can find half stacks as well as stacks that include smaller cabinets. There is even a micro stack that runs on batteries and is designed for the traveling musician. All Marshall amps and speakers are distinguished by their unique "warm" tone and unrivaled overdrive capabilities, which are derived from their use of vacuum tubes instead of transistors.