Convert MIDI file to WAV using fluidsynth on OS X

Question

I'm trying to convert a MIDI file to a WAV file, on OS X.

So far, I have this:

fluidsynth -F output_sound soundfont.sf2 note.mid

This creates an output_sound file, however, that file is not WAV, it seems to be in sint16 format given that I get this output:

~ $ fluidsynth -O help
FluidSynth version 1.1.6
Copyright (C) 2000-2012 Peter Hanappe and others.
Distributed under the LGPL license.
SoundFont(R) is a registered trademark of E-mu Systems, Inc.

-O options (audio file format):
   's16'

Is there an easy way to convert the output_sound to a WAV file in Terminal (or in any scriptable fashion)?

Answer 1

Thanks to CL.'s comment I came up with this:

sox -t raw -r 44100 -e signed -b 16 -c 1 raw_audio audio.wav

Answer 2

There is a simpler way than using SoX: when FluidSynth is installed with libsndfile support, it outputs WAV by default. This is how Homebrew installs FluidSynth by default:

$ brew install fluid-synth
...
$ fluidsynth -T help
FluidSynth runtime version 2.0.8
Copyright (C) 2000-2019 Peter Hanappe and others.
Distributed under the LGPL license.
SoundFont(R) is a registered trademark of E-mu Systems, Inc.

-T options (audio file type):
   'aiff','au','auto','avr','caf','flac','htk','iff','mat','mpc','oga','paf','pvf','raw','rf64','sd2','sds','sf','voc','w64','wav','wve','xi'

auto: Determine type from file name extension, defaults to "wav"

Answer 3

I found the easiest solution to be timidity:

timidity input.mid -Ow -o out.wav

If you use homebrew it's also trivial to install:

brew install timidity