Synthesize MIDI using FluidSynth

Suppose that your soundfont file is example.sf2 and your MIDI file is example.midi:

fluidsynth -ni example.sf2 example.midi -F output.wav -r 48000 -g 1.0

-ni runs FluidSynth in non-interactive mode.

example.sf2 is your soundfont file.

example.midi is your MIDI file.

-F output.wav specifies the output file.

-r 48000 sets the sample rate (you can adjust this if needed).

-g 1.0 sets the gain. The default is 0.2, which causes the audio to be too quiet. 1.0 is a rather balanced value, but can result in clicks in extreme cases.

[Optional] Convert WAV to MP3 using ffmpeg

ffmpeg -i output.wav -codec:a libmp3lame -b:a 320k output.mp3

-b:a 320k sets the audio bitrate to 320 kbps.

References

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