Comment by Dwedit
These are 1992-era MIDI files that came bundled with MIDISoft Recording Session. Note that they contain both "Base" and "Extended" tracks in the same file, so there will be piano notes on channel 16 that are supposed to be percussion. A MIDI player such as Falcosoft Soundfont MIDI Player will detect those kinds of songs and automatically mute channel 16. (There is actually a way to mark channel 16 as a percussion channel, but the people who made those midis in 1992 didn't know about it)