50kHz pitch shifter

[Martin Czech]

:::>And I've heard about people recording bats. Now , tape recorders are made
:::>for the audio band, they will not work. Same applies for most sampling 
:::>technology. Frequency shifting will destroy harmonic relationships.
:::>
:::>Any ideas?
:::
:::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.
:::

Well, most probably the bat sounds are harmonic, after frequency
shifting they will appear like noise... good for detection
but not so good for sampling etc.


:::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. 
:::

right, recording natural phenomena , like the lake example.
Use an ldr for sunlight detection etc. etc.

m.c.