An interestin stereo trick

RevTech

Butthole=output transduce
VIP Junglist
Messages
3,653
Likes
33
#1
Pseudo stereo effects or ’Stereoizers’ create a stereo signal from a source signal which is possibly (but not
necessarily) a mono signal. Actually, many standard effects which are not specifically created to ’stereoize’
such as reverb and chorus will do stereoizing as a side-effect, too. The fact, that various effects have stereo
signals as their output even when their input is mono may make you suspect that dedicated stereoizers may
also utilize different signal processing algorithms to achieve their goal. And this suspicion is right. A very
simple means to stereoize a signal is to delay it a bit (in the range of a few to a few tens of milliseconds)
and mix the delayed signal with positive phase to one channel and with negative phase to the other. Note
that these added delayed signals will cancel each other out in th mono sum. Spectrally, this will result
in comb-filtering both channels with complementary comb-filters. A refinement of this technique is to
modulate the delay over time with an LFO. Another refinement would be to filter the delayed signal in
order to limit the effect to a certain range of the spectrum - it is often desirable to leave low frequencies
untouched (’dry bass’), this could be achieved by highpass-filtering the delayed signal. The delay could
also be replaced by a frequency dependent delay (an allpass filter). Another approach would be to apply
different (complementary) equalization to the left and right channel or use complementary filter banks.
And, of course, one could also combine all these approaches and probably others as well - so, stereoization
seems to offer a lot of room for creativity and experimentation.
 

subprime

Dysjoint
VIP Junglist
Messages
3,085
Likes
94
#2
Another refinement would be to filter the delayed signal in
order to limit the effect to a certain range of the spectrum - it is often desirable to leave low frequencies
untouched (’dry bass’), this could be achieved by highpass-filtering the delayed signal.
Interesting thought, gonna have a play with this one (y) If you used a band pass filter and automated it then the stereo effect might sweep up and down the spectrum? Maybe?
 
Top