An interestin stereo trick

Discussion in 'Production' started by RevTech, Apr 29, 2012.

  1. RevTech

    RevTech Butthole=output transduce VIP Junglist

    Aug 19, 2008
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    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.
  2. subprime

    subprime Dysjoint VIP Junglist

    Feb 2, 2009
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    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?