edge of breakup

Sources use the term to describe the lowest end of a drive or amp's range, often as the starting point that spans up to heavier saturation or fuzz¹²³⁴. It is associated with tube-like response and dynamics, and with tones that respond to playing nuances, such as how hard a player digs in or adjusts the guitar's volume knob⁵⁶⁷⁸. Pedals and amps are frequently described as covering everything from pristine clean through edge of breakup into richer saturation⁹¹⁰.