Mellotron M400


Years of Production1970 – 1977 – Novatron: 1978 – 1986
Number of Unitsabout 2 000
Original Price£795 – Novatron: £1,374
Dimensions L x H x P86 x 86 x 56 cm
Weight55 kg

After the imposing and very heavy Mark II and the lighter but still voluminous M300, the M400 was the first Mellotron whose size and weight allowed it to be carried easily.
The M400 is the most famous and the most widespread of the Mellotrons.

The M400 used 3/8″ tapes and had one single 35 note keyboard (G to F). It didn’t have a rhythm or an accompaniment section anymore, but only solo sounds.

The first M400s had a CMC-10 control card. This card needed a warm up period before the Mellotron could be used to its full effect. Moreover, 6 or 7 notes played at once made the motor slow down, which caused a drop in tuning.
The M400s built from 1973 / 1974 had a SMS-2, which was much more reliable.

The controls were: Volume, Tone, Pitch Control and a track selector.
An input for a volume pedal was available in the front of the instrument.
At the rear, it had a unbalanced 1/4 inch audio output, and on the most recent models (from 1973 / 1974), an balanced XLR output.

The control panel exists in three versions: the most widespread has an aluminium sheet; a rarer version has a black sheet on the M400s commercialized by Mellotronics in London, and a third version has a black sheet with black and yellow knobs, on the M400s commercialized by Sound Sales Inc. in USA (from 1977).

The Mellotron M400 and the Novatron 400 are the same machine; only the name is different (see History).

M400 Mellotrons had a cabinet made of white polished wood. Novatrons 400 were available in black or white.

The way the M400 worked was much simpler than on previous models: the banks with multiple sounds that could be found on Mark II and M300 had been given up and replaced by a removable 35 tape frame.
No more rewind between each bank change – which was a delicate operation for the tapes.
A frame was the equivalent of a bank with 3 sounds; thus, to change a bank, you only had to replace the frame by another frame. Each additional frame was supplied with a flightcase.

Thanks to this removable frame system, a wider range of sounds was available. When you ordered an additional frame, you only had to choose your 3 sounds among those that were available.
With the M400, new sounds appeared. The Choirs, which have now acquired a mythical status, are one of those new sounds.

You could also bring Mellotronics your own sounds, and they converted them to 3/8″ format; this way, you had a personalized sound frame. Steve Hackett recorded his own voice, Paul McCartney recorded bagpipes from the Mull island, as well as various sound effects.

A conversion kit, including tape guides in standard 1/4″ format, was available.
With this kit, you could record your tapes with a standard 2 track tape recorder and use them with your M400 afterwards.

Each M400 was supplied with a volume pedal and a transport cover: The Protecta Muff (Protectomuffs)

Having bought a license from Streetly Electronics, EMI has sold a hundred M400s.
Streetly supplied the Mellotrons in spare parts, EMI assembled them.
The cabinet of these models was in polished wood and their serial number began with E4.
They were very badly assembled, and almost every one of them has been sent back to Streetly to be assembled again.

A left-handed model has been especially made for Paul McCartney; the controls are on the right side of the keyboard.

A Mellotron M400 FX was also available. It was supplied with 12 tape frames including 105 sound effects each.

A M400 with a Plexiglas cabinet was created by Mellotronics for the London Music Expo in 1972.
With this see-through Mellotron, you could see the internal mechanism and the way it worked.
Now this model belongs to David Kean (Mellotron Archives). A second model of this kind was built by Sound Sales in 1977.


M400 #256 & #1671

Photos: David Cilia – 2000


Photos: Klaus Hoffmann-Hoock

Novatron 400 #B1753

EMI 400 #E4-126S

Photos: Klaus Hoffmann-Hoock

M400S Acrylic #1

Photos: Don Kennedy for Studio Bell – National Music Center

M400S Acrylic #2



M400 Owner's Manual
M400 Owner’s Manual
Novatron M400 Brochure
Novatron M400 Brochure
Mellotron USA Catalog 1976
USA Catalog 1976
Sound Sales Inc.
Mellotron Maintenance Procedures - Sound Sales Inc.
Maintenance Procedures
Sound Sales Inc.
Sound List
Mellotronics Limited
French Ad
French Ad


Available sounds at Streetly Electronics

For more information and listen to audio excerpts: Streetly Electronics Mellotron Tape Library

Mk II ViolinsMk II BrassOboe
M400 Violins (eq’d MKII)Muted BrassCor Anglais/Oboe Split
M300BTromboneMkII Flute
Three More ViolinsMixed Brass BVicki Blechta C Flute
String SectionGC3 BrassMkI Clarinet
String Section (No Cello)Two Trombones/Two TrumpetsClarinet-B
Electric String SectionMoog BrassBass Clarinet
New String SectionSoprano SaxPiccolo
Classic StringsTenor SaxRecorder
ViolinAlto SaxOctave Recorders
16 ViolinsTwo Tenor/Two AltoIan McDonald’s Classical Flute
ViolaFrench HornBass Flute
DickstringsGlenn MillerChamber Woodwinds
CelloBaritone SaxWoodwind 2
Paravicini Two CellosChamberlin MutedChamberlin Bass Clarinet
Louise Davis Cello (Vibrato)Trombone
Louise Davis Cello (Plain)Chamberlin Trombone
Louise Davis Cello (Pizzicato)Chamberlin Saxophone
Sad StringsChamberlin Octave
Angry StringsSaxophones
Tony Levin’s NS Electric Cello
Ric Sander’s Electric Violin
Cyndee Lee Rule’s Viola
Chamberlin Violins
Chamberlin Harp
8 Voice ChoirSt John’s Wood ChurchElectric Guitar
Male ChoirOrganSpanish Guitar
Female ChoirPianoSteve Hackett’s Sustained Guitar
Boy’s ChoirM300 PianoAdrian Belew’s Sustained Guitar
Combined ChoirMk I Piano Upper OctavesGordon Giltrap’s Guitar
St Peter’s ChoirsItalian AccordianHarmonics
Russian ChoirRhodesRay Jung’s Fretless Bass
Birotron ChoirMoog Taurus Bass PedalsTwelve String Guitar
Chamberlin Solo FemaleMoog WhooshEbow Guitar
Chamberlin Solo MaleFairlight Arr1Chamberlin Hawaiian Guitar
Fairlight SaxyChamberlin Electric Guitar
Fairlight SwanneeChamberlin Mandolin
Plucked Piano
Hammond C3 Clean
Hammond C3 Dirty
American Pump Organ
Wilden Church Organ
Chamberlin Accordion
Chamberlin Piano
Glocks/Tubular Bells SplitMedieval WoodwindBass Clarinet
CatElectric Guitar
Chamberlin VibesHarp
Hawaiian Guitar
Muted Trombone
Octave Saxophones
Solo Female
Solo Male