If you are looking to CREATE voices, then you want a synth not an arranger. There is very little dark electronica on an arranger. Arranger tend to have very good ACOUSTIC voices.
Most keyboards don't come with software. You can create and change voices on the synth itself.
If you want to create electronic voices on a computer, then you just need a MIDI controller keyboard (the sounds will be produced on your computer with software and a soundcard).
Do a search for Hypersonic 2 on this forum.
Look for posts by Bluezplayer, if you are thinking of creating music with software.
If you're thinking of going the software route you might want to join the Software arranger and softsynth forum here http://www.synthzone.com/cgi-bin/forumdisplay.cgi?action=topics&number=43&SUBMIT=Go
Starkeeper


[This message has been edited by Starkeeper (edited 08-11-2006).]