50kHz pitch shifter

[Fraser, Colin J]

> -----Original Message-----
> From: René Schmitz [mailto:uzs159 at uni-bonn.de]
> Sent: 13 June 2000 16:34
> To: Martin Czech; synth-diy at node12b53.a2000.nl
> Subject: Re: 50kHz pitch shifter
> 
> A few years ago there used to be an article in Elektor 
> describing a device 
> with a balanced modulator that could be used to bring bat 
> sounds into the 
> audio band. I do see the point of the destroyed harmonics, 
> but I can't 
> understand bat language anyway, so the question is if this 
> matters at all.
> 
> And a related thing is the "infra red microphone" which can 
> be used to listen 
> to the sounds of events in light. Like the "sound" of a 
> candle or fire. 

There's a design for a 'Bat Band Convertor' in an old magazine I have too
(EPE IIRC)
The article has descriptions of the different frequency bands and pulse
characteristics for different species of bat.
Might be of interest to bat watchers (or should that be listeners)...
Or maybe you could feature bat vocalists in your music ? Probably sound
better than most chart $hit.

On the subject of infra-red mics - I saw plans somewhere for a 'laser
listener' that uses a reflected infra-red laser beam to pick up any sounds
hitting a window. You could point the listener at any window within your
line of sight, and hear what's being said inside ;-)


Colin f