Here are the modified uLope sub-stages packed into a module that more closely resembles the ADBDR envelope in Hordijk’s Dual Envelope generator.
RH-RM ADBDR Trigger Mode Env.audulus (229.8 KB)
One of innovations in his design lies in replacing the sustain section with second decay stage that can slowly taper off, thus allowing for more ‘natural’ sounding contours. With the decay knob turned all the way up, a conventional flat sustain can be achieved. The second decay is also preceded by a break setting that adjusts how far the first decay falls. The resulting shapes are perhaps most easily understood by taking a look at the diagrams in Hordijk’s schematic.
Each stage also has a modulation input that adds to the values set by the knobs. Since modulation is most effective when the pitch of the modulating waveform is lower than the one being modulated, a sample & hold has been included. Hordijk provides a nice explanation of this technique in the following video: