TheMaartian
I knew I'd seen Square somewhere. Doh!
I've seen Pentagon referenced a few times in the forums. Too bad it's no longer available. Nothing wrong with old (like me!) and simple (not quite like me; yet!).
It seems that Pentagon I was included from Sonar 5 Producer through X3, and was dropped for the rolling update version Sonar(SPlat).
Square I, which was originally a separate download, seems to have been included from Sonar X2 through the current Sonar Splat, etc.
Some observations:
Triangle II - Monophonic, with 2 oscillators, each with 7 waveforms, 1 multi-mode filter, 3 dedicated LFOs, 3 dedicated envelopes ; MIDI learn = yes
Square I - Polyphonic, 3 oscillators, multi-mode filter, 4 LFOs (Pitch, Filter, Volume, and Wave Selector/PWM), 3 dedicated envelopes (pitch, filter, and volume) MIDI learn = no
Pentagon I - Polyphonic, 5 dedicated envelopes (2 amplifier envelopes, 2 filter envelopes, 1 pitch envelope), 4 oscillators, 14 factory waves, 2 multi-mode filters, filter LFO, amplifier LFO, up to 64 voices, MIDI learn = Yes