[rescue] Thoughts on system noise...

[Sridhar the POWERful]

On Sun, 24 Mar 2002, Jeffrey Sharp wrote:

> > I've built these systems. It uses sound of the same wave and amplitude,
> > but opposite phase to cancel the waves out. It's not easy to engineer
> > properly.
>
> I suppose you have to place a microphone at sufficient distance between the
> listener and the source of offending noise, so that there is sufficient time
> to compute and generate the appropriate opposition waveform. I bet it's not
> easy at *all* to engineer properly.

The difficulty is in engineering what to cancel out and what not to cancel
out.

Peace...  Sridhar