Featured MIDI File Player for Linux, Windows, and macOS written in C++, and using Qt5 and Drumstick2.

Features:

• MIDI Output to hardware MIDI ports, or any other Drumstick backend
• Transpose song tonality between -12 and +12 semitones
• Change MIDI volume level (using MIDI CC7)
• Scale song speed between half and double tempo
• Plays Standard MIDI Files (.MID, .KAR) and Cakewalk project files (.WRK)

sourceforge.net/projects/dmidiplayer