Starting in the 1950s, guitarists playing through tube amplifiers noticed that they could make an intriguing new kind of sound by overdriving the amp: a crunchy layer of noise on top of the notes generated by strumming the strings of the guitar itself. This was, technically speaking, the sound of the amplifier malfunctioning, distorting the sound it had been designed to reproduce. To most ears it sounded like something was broken with the equipment, but a small group of musicians began to hear something appealing in the sound.
