zucca (03/20/83)
#R:houxq:-32600:uicsovax:18500001:000:746 uicsovax!zucca Mar 19 12:26:00 1983 The results of such a frequency shift may result in a totally different sound. If there is a linear constant shift of the frequency band then the harmonic relation between the individual spectral components will be lost. For example if there is a harmonic at 100 Hz and then a another harmonic at 300 Hz then a 10 Hz shift will shift the harmonics to 110,310 Hz respectivelyand the since the ratio now is < 3 between the two frequencies then they are not related harmonically anymore, and will probably cause some kind of a 'beat' waveform. This can be avoided if somehow the frequencies are all multiplied by some arbitrary constant and in this way harmonic content is preserved. at U of I Tony Zuccarino
3484ajr (03/23/83)
Frequency Shifter Encompasses Audio Band
This title appeared in EDN October 27 '82 in the
Design Ideas section. To quote Franklin G Fink's
opening paragraph:
You're probably familiar with the techniques used to
shift (heterodyne) two narrow-band frequencies, as in
a superheterodyne receiver. But do you know that you
can shift the entire audio band to obtain interesting
and useful effects? A block diagram ...
I would like to try out his idea and connect the
circuit to my stereo, the telephone, a microphone
(no feedback!), etc.
Has anyone else in net.land ever experimented with
this before?
Contact me if you have an interest in my results.
By the way, the AD534JH Analog Multiplier as
called for can probably be replaced with a
AD533JH ($ 29.95 vs. $ 9.70)
Having fun with analog and audio,
Al Rooney
American Bell
Whippany 3E-338 x3037