Here's something you don't see every day - the under the hood working of a VSTi, but this demo come dissection courtesy of Ourafilmes and Dr SpeakerBlower - the SB-2 polysynth is a construction made using the Windows based SynthMaker program - which allows you to create your own VST instruments and effects "the way you want them". Unfortunately this dev environment only works under Windows and creates Windows only code.
The SB-2 plugin is reasonably priced at £0.00 (free) and SynthMaker Pro will cost you around £200 - but there is also a free version you can get started with.
More From: SYNTHMAKER
Compact, desktop, analog, semi-modular - whats not to like?