This is a very different program to all the others. It is based around a modular synth concept. It has 8 oscillators which can be patched into any of the four accumulators, four multipliers, four sinusoiders and four panaromikers. Each of these takes two inputs and comes out with one output. There are also three ports which generate a square wave, triangle wave and a sine wave from MIDI input. This program does not work like most analog synthesizer programs - it is a lot harder to get a good sound out of it than the other programs. On the other hand this means that it can create sounds that the other non-modular synths can't.
It is possible to load and save configurations and to record to file in the registered version. As with many of these programs that run under Windows there is a slight delay between operating the controls and hearing the results, but with Synthia this isn't too bad. Unfortunately there is a larger (about 1/4 sec) delay between pressing a MIDI key and hearing the result.