The Marshall JC-120, also known as the JCM120 or JC120, is a guitar amplifier head that was introduced in the late 1980s. It's a 120-watt, two-channel amp that features a unique combination of EL34 power tubes and 12AX7/ECC83 preamp tubes. The JC-120 is renowned for its flexibility, allowing players to dial in a wide range of tonal colors, from pristine clean tones to rich, overdriven sounds.
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The preamp section consists of four 12AX7/ECC83 tubes, configured as two channels: The Marshall JC-120, also known as the JCM120