Modern Moog-gear such as the Minimoog Voyager is built with very high quality so it is not every day you get the change of poking around inside one. However, about two weeks ago I got a call from a guy owning a Voyager RME which he claimed didn't sound as it should. The Voyager had previously been repaired under warranty by the dealer who originally sold it. Back from the dealer the problem at first seemed to have been fixed but after playing on it for a while it turned out that every parameter was way off.

Although the Voyager still was under warranty; the owner took the decision to hire me instead of the dealer who originally had repaired it. When I got the Voyager I conducted an initial test and it sounded horribly out of tune. The oscillators didn’t track at all and the output level was almost non-existent. Opening up the Voyager revealed that someone previously had altered every trim-pot in the synthesizer, probably in a desperate attempt to fix the initial problems with it. All trim-pots had markings of being altered and one of the screws attaching the analog-board to the frame was missing.

Going through the Voyager Service Manual it took me about 9 hours to complete the calibrating procedures of the Voyager. Most of the time was however spent on implementing a software tuning application since my hardware tuning device suddenly decided to commit suicide! Being a little rusty on the mathematics of Fast Fourier Transform (FFT) I eventually got the application to analyze the audio input stream from the sound-card. The output of the FFT was then used for calculating a the corresponding note, octave and cents of the main note. The GUI of the application still stinks but as soon as I get time to rewrite it I’ll probably make my little tuning application available for download for those of you who are interested … Please, stay tuned! ;-)