Ubuntu – How does one set up a MIDI keyboard

If you just want to get your keyboard to play sound, this is very simple, and you won't need JACK nor Rosegarden for that. These tools are great if you want to record MIDI signal, write notes, and route audio between separate applications, but you don't need that to play sound with your keyborard.

My step-by-step would be to:

1. Plug in your MIDI device to your computer. If that's a USB MIDI keyboard, just plug the USB, if it has only MIDI plug, you may want to use a MIDI to USB device.

2. Download/Install a synthesizer. There is a large variety of sound synthesing applications for Ubuntu. You may like ZynAddSubFX (really powerful one), FluidSynth or QSynth (support soundfonts), AMSynth, AMS. Make sure to browse Ubuntu Software Center for synthesizer that will grab your interest.

3. Launch the synthesizer. Of course it has to be running to produce sound.

4. Tell the system to pass data from your keyboard to the synthesizer. You need to create a link between your keyboard and your synthesizer, so that MIDI signal is passed to it. You can either use aconnect tool, or one of it's graphical backends (which are simpler to use), like aconnectgui or kaconnect. While aconnect is installed by default, you can get the other two from Software Center. Once you connect your keyboard, and synthesizer, follow to the final step...

5. Press a key on your keyboard. You will hear some sound! If not, make sure if your system sound is not muted, and that our speakers are connected. Also, some synthesizers require you to choose an instrument before they produce any sound.

6. Fine tune your synthesizer settings. You will most likely not enjoy the initial sound of the synthesizer. In case of ZynAddSubFX, this will be a plain sine wave, boring! However, you can easily browse a great collection of timbres, and you can customize them fully. All synthesizers provide you lots of customisation, it's worth to spend some time choosing what you like most.

7. Proceed to play. Good luck and have fun!

I have also once written an article on general workflow for music production with external keyboard on Ubuntu, it should be useful in your case. Here's the link.

If you are able to see your MIDI controller when you run:

lsusb

then this guide should get you set up with the basics. It goes into quite a lot of detail and discusses possible errors you might face and I wouldn't want to skip anything or take credit away from it.

This command should display your controller:

cat /proc/asound/cards

You do not need WINE for any of this.

On Ubuntu 16.04, I then needed to do the following:

Add an audio group to run your software at the right priority:

sudo addgroup audio

Add yourself to the audio group:

sudo adduser $USER audio

Check what address your soundcard is on for output (it's usually hw:0):

aplay -l

Install Fluidsynth and a soundfont which will act as your synthesizer:

sudo apt-get install fluidsynth
sudo apt-get install fluid-soundfont-gm

Install JACK2 which will be the sound server that sits on top of Alsa:

sudo apt-get install jackd2

Run the JACK server, but allow it to bypass any concurrent pulseaudio process:

pasuspender -- jackd -d alsa --device hw:0 --rate 44100 --period 1024

Run the synthesizer with one of the default sounds:

fluidsynth --server --audio-driver=jack --connect-jack-outputs /usr/share/sounds/sf2/FluidR3_GM.sf2

Now check what ports your servers are running on. This should display your MIDI controller(note the number after client, I got 129):

aconnect -i

And this should display the port for Fluidsynth(I got 128):

aconnect -o

Connect the two(remember 129 and 128 are for illustrative purposes, use the port numbers you see in the above two commands):

aconnect 129:0 128:0

You should now be able to hear sounds when hitting the keys on your controller!