SlackBuildsOrg/audio/aseqview

aseqview (ALSA sequencer event viewer)

ASeqView is an ALSA sequencer user-client which works as an event
viewer. It visualizes received events, e.g. note-on/off, controls,
pitch wheels, using bar graphs, as often seen in many sequencer
programs. Using this viewer, even a simple command line sequencer like
pmidi or playmidi1 becomes a cool one with graphical interface :-)

Another feature of ASeqView is redirection of events. ASeqView can
output the received events to subscription ports with some modification
like channel mute or pitch change. Since this works as a real-time
filter client, such modifications can be applied also in real-time
without complexity.