[rescue] Thoughts on system noise...

[Greg A. Woods]

[ On Sunday, March 24, 2002 at 22:01:34 (-0600), Jeffrey Sharp wrote: ]
> Subject: Re: [rescue] Thoughts on system noise...
>
> 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.

There's a retired engineer in England somewhere who thinks he's got the
trick down pat for some kinds of noises like jack-hammers and such.
However he expects that even in production the device will be priced
well out of the range of ordinary people.  Certainly not something you'd
want just to quiet your machine room or office.  Re-designing the fans
and air flow on existing equipment is probably cheaper!  ;-)

(even those headsets often used by pilots that actively cancel sound
instead of just dampening it are damn expensive -- but boy do they ever
work well!)

-- 
								Greg A. Woods

+1 416 218-0098;  <gwoods at acm.org>;  <g.a.woods at ieee.org>;  <woods at robohack.ca>
Planix, Inc. <woods at planix.com>; VE3TCP; Secrets of the Weird <woods at weird.com>