playing a monophonic synth such as the voyager, or any other mono, is tricky but can be mastered.
a monophonic synth can sound like many different things: a bass, a flute, an alien attacking our planet.
when you use a monophonic synth as a bass or lead, it’s worth studying the typical playing techniques of a player of that respective instrument.
i like to think of my moog(s) as singing instruments. i imagine i sing through them. i can’t really sing, but some techniques i tend to employ are vocal techniques, or borrowed from vocal techniques, such as phrasing, pausing, tremolo, vibrato, embellishment, crescendo, portamento, etc. each technique can be effectively used when playing, and it’s cool to have a palette of tricks you can memorize.
when you’re playing the funk, it’s also worth thinking about correct posture: what is the most comfortable and yet economic way of approaching the keyboard? is the piece slow? then sit up, concentrate, and listen to the melody that the dude in your head wants you to play. (works for me. no idea who the dude is, but it’s just an imaginary technique)
Is the piece you are playing fast? then maybe you can sit at an angle, so your arm isn’t uncomfortable.
as for actual playing technique, listen to the masters, but listen also to anything monophonic, such as saxes, flutes, singers, birds, burps, monks, a voice you like, a voice you dislike, etc. lisen to the way ducks quack, car engines rev up, kids scream, a news guy announces the news. anything can find its way into your playing.
also, practice some tunes by playing along with cds you like. when i started out i got a casio vl1 and played along with anything by kraftwerk. their melodies are easy to play along with, and they are funky. soon enough you’ll be finding your own riffs and little melodies or intervals that work cool.
playing an instrument well is a matter of a lot of practice, and trying to make it sound right can be frustrating if technology gets in your way. so it’s a good idea to try out what sounds good in relation to what else is there in the mix. and read the manual…
i also strongly recomment doing a lot of boring stuff: playing scales, figures, or just plaing octaves or other intervals at different speeds, and with different sounds, just to get a feel what’s possible, what works well, and what sounds ugly or inappropriate. do that a lot, and you’ll have no problem with the restrictions of the monophonic synths because you will have learned how important melodies are.
try using effects for cooler, better sound, and compare that to the sound you get when playing dry. never overdo the effects! fingers are great effect units, and those little guys can put out some funny stuff sometimes.
talking of fingers: play with warm hands, or warm em up by stretching em or stiuck em under hot water.
the scale stuff can help players get a better command of their instrument, and will help a lot when you’re improvising, once you can translate the melody in your head straight out to the world without pretzeling your fingers. that’s pretty rewarding!
as a guitarist you might want to do a lot of bending or soloing or some chord work. a monophonic can emulate chords if you have a number of oscillators. this technique can work well, but the chord only ever gets transposed, while you play such sounds. it can screw up your song unless all the chords are meant to be of the same interval. but that technique is fun and always worth a try.