Guy Byars wrote:
Better yet, they ought to develop a STEREO audio vario. Hear the
tone in
your left ear, turn left, or turn right when you hear it in your
right ear.
Even better would be quadra-pnonic... The tone would appear to
eminate from
the center of the lift... left, right, front, or back, you would know
where
the lift was without ever looking at he panel.

Guy Byars

Hey Guy, you must have attended one of my technology forecasts back in
the early 90s ;-) Anyway, what you really want is sonic holography
that gives you not only the direction but distance information.
Requires
a head-tracker and a bit of DSP, now cost-effective except that the
development costs are unlikely sustained by our teeney market...
Best Regards, Dave "YO"