This application allows you to visualize any midi you can upload (upload them using the file dialog on the left saying "Upload file").
Now supports multiple instruments.
With "Change view" you can change, how the notes are visualized.
"Independent channels" mode shows every channel in its own path.
"Merged channels" mode show channels together
(that's how it was in
kpj's
Midi Visualizer).
You can change instruments playing in song's channels.
First choose instruments from dropdown menus, then press "Update instruments".
Try dragging your mouse around the screen or scrolling with your mouse wheel.
You might also want to check one of the following pages for midi files: