Jared ANDERSON
20220207
A way of easing myself back into embedded DSP.
This is meant to be a Parametric Chorus based on that presented by Hal Chamberlin in his Musical Applications of Microprocessors (Second Edition).
He cites the block diagram (Fig. 14-25.) as being taken from notes gathered from a techincal paper delivered by Robert Orban at the 55th convention of the Audio Engineering Society.
I searched low and high for that technical paper but couldn't find it - maybe you can?
This implementation targets the Electro-Smith Daisy Platform on a Pod. Clone this under the DaisyExamples/pod directory and run make to build
The left input of the line-in is used. Stereo output is provided.
There are three pages of menu accessible via the encoder. LED1 shows R, G and B respectively.
R = MIX page
POT1 = Dry/Wet mix
POT2 = Stereo Spread (Odd vs Even bands panned ѕeparately).
G = PHASE page
Button1 - Phase Noise or Phase Shift mode - LED2 toggles Red when in Phase Noise mode, otherwise it's in Phase Shift mode.
In Phase Noise mode - (LED2 Red/Purple)
POT1 = Amount of Noise modulation applied to each band
POT2 = Per Band BW multiplier
In Phase Shift mode - (LED2 Off/Blue)
POT1 = Shift amount (CCW is -ve, 12 o'clock is none, CW is +ve)
POT2 = Per Band BW multiplier
B = DELAY page
Button2 - Delay Noise or Delay OSC mode - LED2 toggles Blue when in Delay Noise mode, otherwise it's in Delay Osc mode.
In Delay Noise mode - (LED2 Blue/Purple)
POT1 = Amount of Noise modulation applied to each band
POT2 = Unused
NOTE: Maybe this needs more work? Sounds gritty.
Updated on 20220529 with reworked random delay noise modulation - no more grit
In Delay Osc mode - (LED2 Red/Off)
POT1 = Delay Mod Rate
POT2 = Delay Mod Depth