From Linux Man Pages
aplaymidi - play Standard MIDI Files
aplaymidi -p client:port[,...] [-d delay] midifile ...
DESCRIPTION
aplaymidi is a command-line utility that plays the specified MIDI file(s) to one or more ALSA sequencer ports.
OPTIONS
-h, --help
Prints a list of options.
-V, --version
Prints the current version.
-l, --list
Prints a list of possible output ports.
-p, --port=client:port,...
Sets the sequencer port(s) to which the events in the MIDI file(s) are sent.
A client can be specified by its number, its name, or a prefix of its name. A port is specified by its
number; for port 0 of a client, the ":0" part of the port specification can be omitted.
For compatibility with pmidi(1), the port specification is taken from the ALSA_OUTPUT_PORTS environment
variable if none is given on the command line.
-d, --delay=seconds
Specifies how long to wait after the end of each MIDI file, to allow the last notes to die away.
RELATED
pmidi(1)
playmidi(1)
CATEGORY