How do I use an ALSA soft synth, such as fluidsynth or Timidity?
Well first, here’s how to get fluidsynth working with a soundfont. First get fluidsynth. Then find a soundfont: one reasonable GM example is Musica Theoria 2, available as mustheory2.sf2 from the Collections area of Hammersound, although it’s large and it’s packed using some stupid Windows-only format (common problem – a few of the soundfonts on there are only zipped, though, so have a look around).