Invented in 1963, the Mellotron was especially prevalent in rock music during the 1960 and 70s. It was used by many groups including The Beatles (featuring heavily on their single, “Strawberry Fields Forever”), as well Pink Floyd and the Rolling Stones.

The distinctive sound of the Mellotron is produced by a bank of thirty-five magnetic audiotapes, one corresponding to each key. Each tape is a pre-recorded strip of a real acoustic instrument that plays for about eight seconds when its key is depressed.

The earliest Mellotrons were bulky instruments with a reputation of unreliability. In acknowledgement of the need of touring rock bands to have portable equipment, the lighter M400 was released in 1970. It quickly became the most popular model produced by Streetly Electronics in the United Kingdom. When the Mellotron trade name was lost to a US company in 1976, Streetly Electronics rechristened the M400 as Novatron, and continued its production until they temporarily ceased business in 1986.

This Mellotron M400 was donated to the School of Music in the 1980s, and became part of the ANU Keyboard Institute in 2007.