Amp channel
An amplifier increases a guitar’s electrical signal in order to reproduce the sound through a connected speaker. Many amplifiers are equipped with separate audio signal paths (aka channels), usually voiced differently to produce a clean sound on one and a more distorted sound on the other.
British amp sound
A catch-all term referring originally to the tones of British amp brands from the 1960s and ’70s such as Marshall and Vox. The former is renowned