Midi output test Utility for external hardware or software synthesizers.
This instrument can generate a gesture so you can hear quickly if the produced sound is the sound you are looking for. The program change dial can be adjusted while playing.
If the choice has been made, you can switch off the gesture and use scores like:
i1 0 2 80 120 ; note 80, velocity 120

My personal Csound command in Ubuntu include the options:
-+rtmidi=alsaseq -Q16
It is making use of the alsasequencer driver, connecting the midioutput -Q to port 16 of my hardware midi output.
aconnect -o shows the right numbers of the midi outputs:
client 16: 'M Audio Delta 1010' [type=kernel]
0 'M Audio Delta 1010 MIDI'

For my external synth i have to substract 1 from the Program Change setting in order to get the corresponding value on my synths' display.
On another synth i found that this substraction was not necessary.

version 3.0, September 2017
- latest GUI (Blue 2.7.0 or greater)

version 2:
- include test button to hear what sound the synth will produce while skipping through the sound banksusing the Program Change dial
- include 4 midi controllers: brightness, filter Q, panning and volume

version 1.0, october 2015