Very useful app ★★★★★

Easy to use app for playing midi files. Can drop individal files, multiple files or folders onto MidiPlayerX (but not folders containing subfolders). When previewing multiple files, the name of only the current file being played is displayed, with arrows to move to next/previous file. To preview files in a large collection, the simplest way is to first Change All midi files to Open with MidiPlayer X (rt-click a midi file, then select Get Info for the option), then simply open a Folder of midi files in Finder, then Double-click each file in turn to preview them.