|
A new type of background sound source for EVP recording When using a radio or taped
voices as the background sound source (BSS) at EVP recording,
there will always be some risks for misinterpretations. Especially
this danger is very obvious with taped voices in experimenter's own
language. To avoid problems, I'd like to suggest a totally
new(?) methode for generating the needed BSS. Because I've not the
possibility to draw any schemes for that, so I have to try to
explain only the basic construction of this new equipment. At
first there are 10 pcs oscillators (e.g. RC coupled
NAND) which each one is connected to a binary divider with
e.g. 8 stages. The outputs of these dividers are summed via a
resistor (about 100..200 kohm). Here is a rough drawing of one
stage of 10: As someone may observe, this
system resembles much the same than used in older electronical
organs. Yes, we might well use the so called basic octave generator
instead. Those basic osc's should be tuned so that the lowest tones
of each respective divider spans e.g.the following frequency range:
(all in Hz) The sum freq. is very rich in formants and thus a band-pass filter is also needed. The band-pass freq. range should be about 300.....3000 Hz. Trim pots are used for fine adjusting the total sound spectra. Another alternative would be the use of several (2..5pcs) parallel coupled formant filters (adjustable) to create human like voices. Also the use of VCF (voltage controlled filter) is possible. In this case a random (ELF) control voltage might be for good.? If you find any sense in this suggestion, so please let me learn your opinions! 4.9.2001
© 2001 Martti Walden
|
||
 |
|
|