The Mellotron (and its direct ancestor the Chamberlin) were in effect the world's first sample-playback keyboards. The heart of the instrument is a bank of parallel linear (not looped) strips of magnetic tape, each with approximately eight seconds of playing time; playback heads underneath (but not directly underneath) each key enable performers to play the pre-recorded sound assigned to that key when pressed. The earlier MKI, and MKII models contained two side-by-side keyboards with 18 selectable sets of specially recorded sounds on the right keyboard such as strings, flutes, and brass instruments which were called 'lead', or 'instrument' sounds, and pre-recorded accompaniment music (in various styles) on the left keyboard. The tape banks for the later, and lighter M-400 models contain three selectable sounds (per changeable taperack) such as strings, cello, and the famous eight voice choir. The sound on each individual tape piece is recorded at the specific pitch of the key that it was assigned to. When the tape reaches the end, it stops and rewinds to prepare to play the note again.
Although tape samplers had been explored in research studios (e.g., Hugh LeCaine's 1955 keyboard-controlled 'Special Purpose Tape Recorder', which he used when recording his classic 'Dripsody'), the first commercially available keyboard-driven tape instruments were built and sold by California-based Harry Chamberlin from 1948 through the 1970s.
Things really took off, however, when Chamberlin's sales agent, Bill Fransen, brought two of these remarkable devices to England in 1962 to search for someone who could manufacture 70 matching tape heads for future Chamberlins. Chamberlin was not at all happy at first with the fact that someone overseas was basically 'copying' his idea, and that one of his own people (Bill Fransen) was the reason for this. He eventually found a UK company that were skilled enough to develop the idea further and a deal was struck with Bill and Lesley Bradley of Birmingham-based tape recorder company, Bradmatic Ltd. who themselves had a great electronic tape recording manufacture history, this resulted in the formation of a subsidiary company named Mellotronics in Birmingham which produced the first Mellotrons. Bradmatic later took on the name Streetly Electronics (also of Birmingham); many years later following financial and trademark troubles, the Mellotron name became unavailable and later instruments were traded under the name Novatron. A small number of the instruments was assembled and sold by EMI under license.
The first Mellotrons were called Mk.I's and soon were upgraded with new sounds to the Mk.II. The Mk.II has two keyboards. The right hand keyboard has instrument sounds, such as a flute, piano, mandolin, and saxophone. The left hand keyboard (rarely used on pop albums) was designed as a 'rhythm section' with recorded ensembles playing in different styles such as jazz, foxtrot, waltz, etc. Through the late 1970s, the Mellotron had a major impact on rock music, particularly the 35 note (G-F) M-400 which was released in 1970 and sold over 1800 units, becoming a trademark sound of the era's progressive bands. The M400 was compact, but had fewer sounds. It was more reliable than the Mk.II model, but still prone to trouble.
Mellotrons were normally pre-loaded with string instrument and orchestral sounds, although the tape bank could be removed with relative ease by the owner and loaded with banks containing different sounds including percussion loops, sound effects, or synthesizer-generated sounds, to generate polyphonic electronically generated sounds in the days before polyphonic synthesizers. The unique sound we associate with the Mellotron is produced by a combination of characteristics of tape replay such as wow and flutter, the result being that each time a note is played it is slightly different from the previous time it was played (a bit like a real instrument). The notes also interact with each other so that chords or even just pairs of notes have an extremely powerful sound. The novel characteristics of the instrument attracted a number of celebrities and among the early Mellotron owners were Princess Margaret, and Peter Sellers.
Although they were highly prized and enabled many bands to perform string, brass and choir arrangements that had been previously impossible to recreate live, Mellotrons were not without their disadvantages. Above all, they were very expensive, the official Mellotron site gives the 1973 list price as US$5200. And like the Hammond organ they were a roadie's nightmare, heavy, bulky and fragile. The tape banks were also notoriously prone to breakages and jams and those groups who could afford to typically took two Mellotrons on tour with them to cope with the inevitable breakdowns, however the machines were the forerunner to the sampler. Mellotrons were not intended to be portable (they often become misaligned even when lightly jostled), and when installed permanently in a studio they provide a very realistic effect.
The Mellotron was first made famous by the Beatles, who used it prominently on their groundbreaking 1967 single 'Strawberry Fields Forever', and it was also used by the Zombies, the Moody Blues ('Nights in White Satin'), the Rolling Stones ('2000 Light Years from Home', 'We Love You', 'Stray Cat Blues'), Donovan ('Celeste', 'Breezes of Patchule'), Pink Floyd and others during the psychedelic era. Rolling Stones guitarist Brian Jones was supposedly the first musician to master the instrument.
The Mellotron was widely used to provide backing keyboard accompaniment by many of the progressive rock groups of the 1970s and alongside the venerable Hammond organ it was crucial to shaping the sound of the genre. It features on albums such as In the Court of the Crimson King by King Crimson, Fragile and Close to the Edge by Yes, and Foxtrot and Selling England by the Pound by Genesis.
John Paul Jones of Led Zeppelin used a Mk.II. Mellotron to recreate the flute intro arrangement for live performances of 'Stairway to Heaven', from Led Zeppelin IV. The Mk.II. was introduced, beginning with the Japanese Tour of 1972. It is featured prominently on the Houses of the Holy track 'The Rain Song'. The complex Eastern orchestral sounds of 'Kashmir' were handled by the M400, which replaced the Mk.II. Jones explained in Keyboard magazine: 'To walk up to the Mellotron, not knowing if it was going to be in tune or what it was going to do, was a terrifying experience! Indeed, many Mellotrons had badly designed motor control cards. This would cause the instrument to drift in pitch and sometimes fail.
For the 1977 tour, Jones played Jimmy Page's Mk.V Mellotron, a rare protype of the Mk. V model that was actually two M400s in one unit. It was wide and black, and allowed twice as many sounds inside. Having two keyboards also allowed greater performance options since two sounds could be played simultaneously. Unfortunately, the Mk.V was no more reliable than the M400, and it was replaced with synthesized strings on the 1979 tour.
The advent of cheaper and more reliable polysynths and preset 'string machines' saw the mellotron's popularity wane by the end of the 1970s.
The Mellotron sound returns
Although it appeared to have been rendered obsolete by polyphonic synthesizers and digital sampler keyboards, the distinctive sounds of the Mellotron proved to have a lasting appeal and in the 1990s some bands began using refurbished Mellotrons in order to re-create a 1970s progressive rock atmosphere. Many bands and producers also regularly use digital samples based on Mellotron sounds, and a new Mellotron model has recently been produced. Pearl Jam's Riot Act album (2002) featured heavy use of the Mellotron. The Mellotron has also been resurrected in a new form by GMedia who have created a simulation of it for electronic music, including digitisations of the original tape banks.