Vortex Tracker II is a Win32 tracker used to make music for the AY-3/YM series of sound chips. This is the sound chip used in the ZX Spectrum and Atari ST home computers, among other things. It can export a wide variety of formats for playback on real hardware. Vortex Tracker II can also synchronize two open modules to emulate dual AY playback.
Tutorial by BotB's own ant1!
Vortex Tracker II fan art