M-Tron Keyboard

The Original Instrument



It may come as a surprise to some of you that we don’t own a real Mellotron® anymore.

Why? Because we got fed up with trying to keep the thing in tip-top working condition as well as trying to create music. With our real Mellotron® it was often a case of “Quick, record that track while the Mellotron’s working” So now we prefer to use the M-Tron and leave the Mellotron® maintenance headaches to others.

Sadly though, when we sold our Mellotron® we also gave the new owner all the associated documents that we’d build up over the years so we’re unable to fill this page with the usual gear porn and collector type trivia.

So instead here’s some pics showing some of the fun and games to be had when changing tapes - not a job for the faint-hearted - as well as a link to a Sonicstate video where the Mellotron® was voted thirteenth in their Top Twenty Synths poll.


1. Controls


It’s not the most complex of instruments to operate, but changing tape-frames is an art in itself.


2. Topless


A Mellotron® with its lid off. The next step in replacing the tapes is to remove the keyboard mechanism.

3. Tapes


Once the keyboard has been removed, we can then remove the tapebank frame.

4. Tape Frame


The frame which houses the tapes associated with the 35 notes of the instrument.

5. Re-Threading


With 35 notes to deal with, re-threading a new set of tapes can take an eternity for the unskilled. With two people we managed to get this down to 35 minutes per tapebank.
Mellotron® Alternatives

It’s reasonably well known that the Mellotron® was derived from the US made Chamberlin but little is known about the Birotron® that followed both these instruments.

The Birotron was a joint-venture between Rick Wakeman and Dave Biro and was an attempt to overcome the Mellotron’s 8 second note limitation and its issue of portability.

In an attempt to overcome both issues the Birotron used 8-Track cartridges which in effect created an indefinite loop. Naturally these being smaller than the tape-frame needed for the Mellotron® meant that the portability issue was largely solved too.

However, a major drawback was revealed in that because of the constant movement of the tape within the cartridge, the Birotron was very noisy and tape wear could be excessive.

The Birotron is a classic case of good product at the wrong time and Rick Wakeman makes no secret of the fact it was a financial disaster and although there’s a debate as to whether 30 or 50 were produced, the only album we are aware of it being used on is the Yes Tomato album.

We were fortunate enough to locate one and naturally recorded the sounds for use in the M-Tron.



The slightly more portable Birotron

Front Panel



The Birotron controls with a scribble-strip for the four (yes, four) sounds, plus volume, attack & decay controls.

Finally there’s a rather sexy Vernier pot for the pitch control Inside


The inside of a Birotron showing the groups of 8-Track cartridges



Cartridges were accessed from the rear of the instrument but were grouped according to specific notes.

Sadly, if you had a cartridge fail it was almost impossible to work out exactly which specific notes these were until you tried to play them.

Legal Notice
All product names used in this product are trademarks of their respective owners and are in no way associated or affiliated with GForce Software Ltd. These trademarks of other manufacturers are used solely to identify the products of those manufacturers whose tones and sounds were studied and or recorded during development of this product.