Windows & Mac
The Dexed synth plugin is an FM VST (meaning frequency and modulation).
It work with Windows as well as with Mac (VST & AU), so both operating systems are good to go with this one.
It’s modelled after the famous synthesiser called DX7 from the brand Yamaha.
Although it’s free, it truly is something useful to create your own sounds.
You can also use the library that comes with it.