So I have just purchased Tie Fighter on GoG and I have been trying the CD collector version. The sound effects are fine but the music is awful, i.e. nowhere near the quality of what you can heat on YouTube videos,

In the install menu (configuration), I picked Sound Blaster 16 for sound and music. I can't pick any other option for the music (otherwise the music won't play).

The game is running with Dosbox for Ubuntu 18.04

Any advice?

Take into account that those YouTube videos you are watching are probably using MIDI music.

Take a look at the pinned topic of this forum, it is not just for X-Wing despite the lack of mention of Tie Fighter in the first post. But read the rest of the topic, there are explanations on what is best to do for each game and version of the game.

After following those instructions to use VirtualMIDISynth and a proper soundfont, in order to configure the game to use it you have to:

- Enter the Sound Settings program and do what you already have (press the 'Install' button and then the 'Set up Sound Card' button)
- Press the 'C' key
- Leave the sound card options as they are, SB16 for sound is as good as you will get (sadly DOSBox does not emulate AWE32)
- Go down to the 'Advanced Menu' option
- That separates music and sound options, so we will focus on the left side (music)
- Choose 'General MIDI' in Music, and 330 in Port
- Test the music. If VirtualMIDISynth is running and has a soundfont loaded, it should sound a whole lot better than DOSBox's FM emulation.

Thanks for that. I discovered that pinned topic just after I posted my question. However I am not sure I can implement it in Ubuntu! I'll have a look.

Any program to load MIDI soundfonts should work as long as TF is set up in DOSbox as General MIDI for the music (you can run directly the imuse or setmuse file from inside DOSbox).
When you find a good MIDI soundbank loader for Ubuntu I strongly recommend Timbres of Heaven as a soundbank, it really brings forth that "variation on the ROTJ dark side theme" vibe a lot of the music of the game has.

What you are looking for then is FluidSynth. From my experience with it from its implementation in ScummVM it's pretty good.

You also have Munt for Linux, in the case those select games that were developed for Roland synths and sound better in them than in General MIDI, like X-Wing for example. For this one you need the ROM dumps from the real devices, which is not strictly legal if you don't own them, but...

I have some Linux experience but not enough to help you in this case. It looks as if its trying to use JACK as server and you don't have it installed? :-?