Using the MK14 as a synchronised rhythm generator
When I built my MK14 in the autumn of 1979 I was already heavily into electronics and electronic music. I had been bitten by the synthesizer bug after buying Jean Michel Jarre's 1976 album Oxygene and dreamed of following in his footsteps. Unlike Jarre, however, I didn't have a lot of money, and like so many musicians do, I had to make do with what I could afford. That usually meant making things myself. The previous year, I had adapted circuits from Practical Electronics magazine and built my own analogue synthesizer. The keyboard came from an old child's mechanical organ, and I made the case out of wood. This synth was monophonic, a little out of tune, and although it could make some interesting sounds, it lacked the ability to be synchronised with drums or a sequencer.
The worst problem I faced as a budding musician was that of having somewhere to record the music. This was long before MIDI; affordable digital recording was still only a dream, and audio recording meant buying an expensive multi-track open reel tape recorder. Instead, I used a domestic open reel machine (I was never without one from the age of about 8) and of course I had to adapt it. I found that by disconnecting the erase head, I could record many music tracks over the top of each other, building up a chorus from a single instrument. Unfortunately, recording over a track had the effect of muffling the tracks underneath, and the effect got worse with the number of overdubs. The solution was to record the more bass sounds first, and the top layer would be the brightest sounds, for example drums. The trouble is, I needed to record the drums first because they set the rhythm for the whole piece. I was stuck.
Enter the MK14
After building and learning to program the MK14, I found that it made an ideal synth controller. In fact, I adapted a drum-box circuit from Practical Electronics and connected it to the MK14's 8-line output port. One line controlled each drum. It was fairly simple; a few hi-hats, a bass drum, a cymbal (hiss) and a couple of bongos (damped sine waves). Suddenly I had my own rhythm computer (just like Jarre!) but I still had the problem of synchronising it with the music I was going to lay it over. The MK14 came to the rescue once again. I used the cassette interface to respond to a series of pre-recorded pips on an unused track of my 4-track machine. First I recorded the (MK14-generated) pips on the reverse side of the tape. Then I recorded the music while using the pips as a metronome. Each track built up on top of the previous one, and finally I added the drums by using the pips as a synch signal for the MK14. It worked like a dream. I was also able to build a simple sequencer and synchronise that to the MK14 as well. The only problem was that sometimes, for example when the fridge downstairs switched on or off, a spurious click would knock the synch out by one beat. My equipment was not shielded; at the time I didn't fully understand the need for shielding.
Using the MK14 as a synchronised rhythm generator