Marshall 1959

The Marshall Super Lead Model 1959 is a guitar amplifier head made by Marshall. One of the famous Marshall Plexis, it was introduced in 1965 and with its associated 4×12" cabinets gave rise to the "Marshall stack".

The 1959 (Marshall's identifying numbers are not years of manufacture) was produced from 1965 to 1981 (when it was replaced by the JCM800), is an amplifier in Marshall's "Standard" series. It was designed by Ken Bran and Dudley Craven after The Who's guitarist Pete Townshend asked Marshall for a 100 watt amplifier. Its output was first channeled into an 8×12" cabinet, but that single, unwieldy cabinet was quickly changed to a set of 4x12" cabinets, creating the "Marshall stack". The amplifier also came as a PA and a bass version.

The Plexiglas panel led to the name "Plexi", and while 50-watt models of the time are also called Plexis, the 1959 100 watt model is generally thought of as the "definitive" Plexi.

In 1969, Marshall replaced the Plexiglas panel with one of gold aluminum. There were other modifications: In 1966, the KT66 tubes of the JTM-models were replaced with EL34. After 1976, the plate voltages were lowered slightly for improved reliability. But during the 1970s, Marshall's increasing exports overseas led to a problem: Often the EL34 tubes would break during transportation, to the point where amps began being shipped from the factory with more rugged Tung-Sol 6550 tubes, which are "stiffer and not as harmonically rich" as the EL34 tubes.

The amplifier was reissued for the first time in 1988 (the 1959S), and again from 1991 to 1993 (the 1959X) and from 1993 to 1995 (the 1959 SLP). In 2005, Marshall introduced the 1959 HW (for "hand-wired"), based on the 1967–1969 models, with negative feedback added corresponding to the 1969 model. This amplifier was called "expensive but good".Guitar Player magazine called the 1959 "monumentally huge, frightfully loud, and painfully expensive", and its review of the 1959HW said it was "quick, percussive, articulate", and required a "total commitment to volume".

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