Earlier quoted context omitted.
There is no "correct" sound for a MIDI file In the case of canyon.mid there is because it was composed for a specific midi instrument with a particular set of timbres. Or to put it another way, it’s music and therefore complicated.
I can play the guitar parts on a banjo but it ain't going to sound right.
QRS is still in business and some of its product lines use Midi conversions of piano rolls and last month I landed a mixed lot with a bunch of those Midi files on 3.5” floppy disks.
I had George Gershwin rocking a Yamaha XG clavichord and Liberace on a Sitar and similar shenanigans.