I imagine them as a four piece - two humans and two robots.
Drum machine: Robot 1
Bass machine: Robot 2
Singer/Guitarist: Human (Any chance he could look a bit like me? Curse my vanity!)
Ambienz: Female Human
I imagine them dressed in quite tight-fitting white clothes, with the stage mostly in shadow. Various implants for the humans.
The Drum machine is similar to some of the huge drum kits people like Nick Mason have used - i.e. surrounded by drums. Except here the robot (whose four arms each have three joints, the last section being a drumstick) is completely surrounded by a spherical mesh of semi-transparent round holographic projections, each of which triggers a sound when "hit".
The bass machine is similar in concept - either four or six holographically projected lines which are "plucked" in front of the robot, as if he were weaving. The robot has three arms - two for plucking and one with (4 or 6) long fingers, each with a mirror that shortens the beam of light, to create the pitch of the note.
The Ambienz provides synth-like sounds. However, it is not controlled directly. The brainwaves of a certain area of the player's brain are scanned, and this information in converted into sound. It's a very hard instrument to master! The Ambienz player sits in a semi-spherical container, with a holographic projection of his output that he can tweak physically if neccesary.
But i imagine this is the kind of precise answer that atrists hate! Do whatever you imagine at the end of the day - it's not like i have a monopoly on Jjagged Bbanner!