🚀 go-pugleaf

Well, by "light show" you apparently mean oscillators-talking-to-some-kind-
of-deflection-system.  This is really only part of a decent full-blow show..
anyway, the canonical [albeit expensive] route is to find General Scanning
galvanometers and drive them with some kind of amplifier.  I don't know about
the commercial unit you mentioned [if you have more info on it, could you
send it along?  The price seemed awfully low] but I do know about the
"Laser F/X" thing being marketed by your local yuppie stores -- it isn't a
laser, they're using *one* bouncing mirror for deflection, and you could
throw one together for about $5.  Don't buy it.  Anyway, speaker-based
kludges will work but will never give you the linearity and repeatibility
that real galvos will.  An alternative is small stepper motors, 90-degree
if you can get 'em, with a holding voltage on one coil and your signal going
to the other.  [You also might want some form of mechanical restraint so it
doesn't "wrap around" on strong pulses.]  Check for loose bearings...

Professional shows use multiple x-y pairs of GS's better positional-feedback
galvos -- they're not only fast as hell, they provide exact feedback about
where they are, and you can build your driver accordingly.  They also cost
something like $700 per.  Since GS is apparently still the only company
making these things [someone please correct me if I'm wrong] they can get
away with this pricing scheme.

I've always been generally irked at the prices these manufacturers are
getting for laser equipment.  They *can't* cost that much to build...

_H*