uPop DX Phase Modulation Operator


uPop DX

The uPop DX is a single phase modulation operator similar in concept to the operators used in the Yamaha DX7. It outputs a sine wave which can be phase modulated. It has a 1 per octave input, 3 phase modulation inputs, a feedback input, a sync input, course and fine frequency ratio controls, a detune control, feedback control and an output level control. Unlike the DX operators, in order to conserve screen space and CPU cycles, it has no internal envelope or keyboard tracking. It is typically used in multiples to construct various phase modulation algorithms. (see demo). The Variable Curve ADSR Envelope Generator is one possible EG that can be used to modulate the uPop. The feedback input is designed to allow feedback either from the module itself or another module later in the chain. The feedback input has an internal unit delay (z-1) to prevent the one frame delay that would otherwise be inserted in the loop.


Input Signal Range Notes
o%20input 1 per octave oscillator frequency
p%20input audio signal -1 to 1 phase modulation input
fb%20input audio signal -1 to 1 feedback signal
s%20input 0 - 1 trigger sync input - syncs internal oscillator

Output Signal Range Notes
audio%20output audio signal -1 to 1 audio out to output or phase modulation input


[Knob, Button, Spline, and/or Mapper] Function Notes
feedback%20knob feedback level attenuator for feedback signal
level%20knob output level output level adjust
ratio%20knob frequency ratio course and fine frequency ratio controls - fine control is in 0.01 increments
detune%20knob detune detunes oscillator + or - 0.5 semitone in 0.01 increments


Meter Displays Notes
ratio%20display frequency ratio
detune%20display detune amount semitones - light indicates no detune

Version History

Revision File Date Notes
1.0 uPop DX V1.0.audulus (24.3 KB) 05/04/2018 initial upload to new forum


Revision File Date Notes
1.0 uPop DX V1.0 demo.audulus (717.3 KB) 05/04/2018 initial upload - demo is a basic PM synth wired with a chain of 3 operators in parallel with one additional operator.

This is great! Thanks for sharing!

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