Linux is excellent at many things. At midi it is not. Playing midi music in Windows is easy. In Linux it is hard, but Linux has the advantage of having a lot of free software and with Ubuntu a lot of that free software is easily installed. Among these free software applications is a program called Nted which makes writing sheet music easy. The problem is midi audio output for your sound card will not work correctly in Linux unless you do a couple of things.
In Ubuntu go to the Ubuntu Software Center and install Timidity and QjackCtl (Jack Control) which will help with getting midi working.
To get timidity midi running go to the terminal and use the command…
That will give you a sequencer port number (usually 130). Then run program you want to use like nted, then run jack and connect the program you want to use to timidity 130.
Then install Nted through the Software Center. Make sure you’ve recently rebooted (once a midi setup in Linux does not work correctly it is hard to get any sound working correctly until you reboot) and run both programs simultaneously. In Qjack press the Connect button and go to the ALSA tab. Click in the left panel where it says NTed to highlight that and then highlight Timidity in the right panel and press the connect button. Now you can use your audio card to output the stuff you are composing in Nted. Midi in Linux is a pain in THE BUTT!
I noticed that adding measures in Nted is not as described in the online source I found. That source says that you are to select a note and then use Insert – Insert Block. That does not work (I think it’s only for adding measures until that line of the score runs out). Instead use Insert – append a system at the end (shortcut key Ctrl+b).