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This document has the same layout as the manpage, but it contains links to other pages for more information: FluidFeatures and FluidSettings. It may however be not as up to date as the manpage shipped with fluidsynth.
FluidSynth - a SoundFont synthesizer
fluidsynth [options] [ SoundFonts ] [ midifiles ]
FluidSynth is a real-time MIDI synthesizer based on the SoundFont® 2 specifications. It can be used to render MIDI input or MIDI files to audio. The MIDI events are read from a MIDI device. The sound is rendered in real-time to the sound output device. See FluidFeatures for a comprehensive list of features implemented and working.
The easiest way to start the synthesizer is to give it a SoundFont on the command line:
fluidsynth output.sf2. fluidsynth will load the SoundFont and read MIDI events from the default MIDI device using the default MIDI driver. Once FluidSynth is running, it reads commands from stdin. There are commands to send MIDI events manually, to load or unload SoundFonts, and so forth. All the available commands are discussed below.
FluidSynth can also be used to play a list of MIDI files. Simply run FluidSynth with the SoundFont and the list of MIDI files to play. In this case you might not want to open the MIDI device to read external events. Use the -n option to deactivate MIDI input. If you also want to deactivate the use of the shell, start FluidSynth with the -i option:
fluidsynth -ni soundfont.sf2 midifile1.mid midifile2.mid.
Run fluidsynth with the --help option to check for changes in the list of options.
fluidsynth accepts the following options:
The audio driver to use. "\\-a help" to list valid options
Turn the chorus on or off [0|1|yes|no, default = on]
Number of audio buffers
Dump incoming and outgoing MIDI events to stdout
Audio file endian for fast rendering or aufile driver ("-E help" for list)
Load command configuration file (shell commands)
Render MIDI file to raw audio data and store in [file]
Defines the number of LADSPA audio nodes
Set the master gain [0 < gain < 10, default = 0.2]
Print out this help summary
Don\u2019t read commands from the shell [default = yes]
Attempt to connect the jack outputs to the physical ports
The number of midi channels [default = 16]
The number of stereo audio channels [default = 1]
Don\u2019t connect to LASH server
The name of the midi driver to use [oss,alsa,alsa_seq,...]
Don\u2019t create a midi driver to read MIDI input events [default = yes]
Audio file format for fast rendering or aufile driver ("-O help" for list)
Define a setting, -o name=value ("-o help" to dump current values). See [FluidSettings] for details
Set MIDI port name (alsa_seq, coremidi drivers)
Turn the reverb on or off [0|1|yes|no, default = on]
Set the sample rate
Start [FluidSynth] as a server process
Show version of program
Audio file type for fast rendering or aufile driver ("-T help" for list)
Print out verbose messages about midi events
Show version of program
Size of each audio buffer
All settings are non-realtime (have no effect if set after startup), except for those indicated as realtime.
synth.audio-channels INT [min=1, max=128, def=1] Number of audio channels (DOCME!).
synth.audio-groups INT [min=1, max=128, def=1] Number of audio groups (DOCME!).
synth.chorus.active BOOL [def=True] Chorus effect enable toggle.
synth.cpu-cores INT [min=1, max=256, def=1] Number of CPU cores to use for multi-core support.
synth.device-id INT [min=0, max=126, def=0] REALTIME Device ID to use for accepting incoming SYSEX messages.
synth.dump BOOL [def=False] No effect currently.
synth.effects-channels INT [min=2, max=2, def=2] No effect currently.
synth.gain FLOAT [min=0.000, max=10.000, def=0.200] REALTIME Master synthesizer gain.
synth.ladspa.active BOOL [def=False] LADSPA subsystem enable toggle.
synth.midi-channels INT [min=16, max=256, def=16] Total MIDI channel count (must be multiple of 16).
synth.midi-bank-select STR [def='gs' vals:'gm', 'gs', 'xg', 'mma'] MIDI Bank Select message style.
synth.min-note-length INT [min=0, max=65535, def=10] Minimum duration for note events (work around for very short percussion notes).
synth.overflow.age FLOAT [min=-10000, max=10000, def=1000] Weighting (on overflow) for a voice's duration.
synth.overflow.percussion FLOAT [min=-10000, max=10000, def=4000] Weighting (on overflow) for a voice being on the drum channel.
synth.overflow.released FLOAT [min=-10000, max=10000, def=-2000] Weighting (on overflow) for a voice that has been released, i.e., note off and no sustain pedal.
synth.overflow.sustained FLOAT [min=-10000, max=10000, def=-1000] Weighting (on overflow) for a voice that has been sustained, i.e., note off, but sustain pedal held down.
synth.overflow.volume FLOAT [min=-10000, max=10000, def=500] Weighting (on overflow) for a voice's volume.
synth.parallel-render BOOL [def=True] Enables low-latency audio rendering response, even if synth is otherwise busy. Should always to be true for usage by fluidsynth executable.
synth.polyphony INT [min=1, max=65535, def=256] REALTIME Voice polyphony count (number of simultaneous voices allowed).
synth.reverb.active BOOL [def=True] Reverb effect enable toggle.
synth.sample-rate FLOAT [min=22050.000, max=96000.000, def=44100.000] Synthesizer sample rate.
synth.threadsafe-api BOOL [def=True] Serializes access to the synth API. Must always to be true for usage by fluidsynth executable.
synth.verbose BOOL [def=False] Print received MIDI events to stdout.
audio.driver STR Audio driver to use. Default and valid options depend on available drivers.
audio.input-channels INT [min=0, max=2, def=0] Not used currently? (DOCME).
audio.output-channels INT [min=2, max=32, def=2] DOCME
audio.period-size INT [min=64, max=8192, def=64] Period size for audio buffers. Used by many audio drivers.
audio.periods INT [min=2, max=64, def=16] Count of audio buffers. Used by many audio drivers.
audio.realtime-prio INT [min=0, max=99, def=60] Realtime priority to assign to audio thread or 0 to disable high priority scheduling. Only used by some audio drivers (currently 'alsa' and 'oss').
audio.sample-format STR [def='16bits' vals:'16bits','float'] Audio output format, to select format for those drivers which support 16 bit or floating point.
AUDIO DRIVER SPECIFIC
audio.alsa.device STR [def='default'] ALSA audio driver output device.
audio.coreaudio.device STR [def='default'] CoreAudio? driver output device. Valid options depend on system.
audio.dart.device STR [def='default'] OS/2 Dart audio driver device.
audio.dsound.device STR [def='default'] Device to use for DirectSound? driver. Valid options depend on system.
audio.file.endian STR [def='auto' vals:'auto','big','cpu','little'] File renderer or file driver byte order selection. 'auto' selects the default for the selected file type. 'cpu' uses the CPU byte order. Limited to 'cpu' if no libsndfile support.
audio.file.format STR [def='s16' vals:'double','float','s16','s24','s32','s8','u8'] File renderer or file driver audio format. Limited to 's16' if no libsndfile support.
audio.file.name STR [def='fluidsynth.wav'] Output file name for file renderer or file driver.
audio.file.type STR [def='auto' vals:'aiff','au','auto','flac','oga','raw','wav'] Output file type for file renderer or file driver. 'auto' attempts to determine type from file extension in audio.file.name. Limited to 'raw' if no libsndfile support. Actual options will vary depending on libsndfile library.
audio.jack.autoconnect BOOL [def=False] If enabled, then [FluidSynth] is automatically connected to Jack system audio output ports.
audio.jack.id STR [def='fluidsynth'] Client ID to use when connecting to Jack.
audio.jack.multi BOOL [def=False] TRUE to enable multi-channel output.
audio.jack.server STR [def=] Jack server name. Blank for default.
audio.oss.device STR [def='/dev/dsp'] OSS driver output device.
audio.portaudio.device STR [def='PortAudio Default'] [PortAudio] driver output device. Available options depends on system.
audio.pulseaudio.adjust-latency BOOL [def=True] Increases the latency dynamically if PulseAudio? suggests so.
audio.pulseaudio.device STR [def='default'] PulseAudio? driver output device.
audio.pulseaudio.media-role STR [def='music'] PulseAudio? media role information.
audio.pulseaudio.server STR [def='default'] PulseAudio? driver server.
midi.driver STR MIDI driver to use. Default and valid options depend on available drivers.
midi.realtime-prio INT [min=0, max=99, def=50] Realtime priority to assign to MIDI thread or 0 to disable high priority scheduling. Only used by some MIDI drivers (currently 'alsa_seq', 'alsa_raw' and 'oss').
MIDI DRIVER SPECIFIC
midi.alsa.device STR [def='default'] ALSA raw MIDI driver device.
midi.alsa_seq.device STR [def='default'] ALSA sequencer MIDI driver device.
midi.alsa_seq.id STR [def='pid'] ALSA sequencer client ID. 'pid' will use process ID as part of the client name.
midi.coremidi.id STR [def='pid'] Client ID to use for CoreMIDI driver. 'pid' will use process ID as port of the client name.
midi.jack.id STR [def='fluidsynth-midi'] Jack MIDI driver client ID.
midi.jack.server STR [def=] Jack MIDI driver server. Blank to use default.
midi.oss.device STR [def='/dev/midi'] OSS MIDI driver device.
midi.portname STR [def=] Port name used for CoreAudio? and ALSA sequencer drivers.
midi.winmidi.device STR [def='default'] Device for Windows MIDI driver.
player.reset-synth BOOL [def=True] TRUE to reset synthesizer MIDI state between MIDI songs.
player.timing-source STR [def='sample' vals:'sample','system'] Selects timing source for MIDI sequencer. 'system' uses the system timer. 'sample' uses the sample clock (amount of audio output, events synchronized with audio).
shell.port INT [min=1, max=65535, def=9800] Shell command server TCP/IP port number to use.
shell.prompt STR [def=] Shell prompt string.
Prints out a summary of the main commands
Prints out list of other help topics (type "help <topic>")
Quit the synthesizer
Load a [SoundFont]
Unload a [SoundFont]. The number is the index of the [SoundFont] on the stack.
Lists the current SoundFonts on the stack
Print out the available instruments for the [SoundFont].
noteon channel key velocity
Send a note-on event
noteoff channel key
Send a note-off event
cc channel ctrl value
Send a control change event
prog chan num
Send program-change message
select chan sfont bank prog
Combination of bank-select and program-change
Print out the presets of all channels.
Set the master gain (0 < gain < 5)
Choose interpolation method for all channels
interpc chan num
Choose interpolation method for one channel
Turn the reverb on or off
Load preset num into the reverb unit
- num:0 roomsize:0.2 damp:0.0 width:0.5 level:0.9
- num:1 roomsize:0.4 damp:0.2 width:0.5 level:0.8
- num:2 roomsize:0.6 damp:0.4 width:0.5 level:0.7
- num:3 roomsize:0.8 damp:0.7 width:0.5 level:0.6
- num:4 roomsize:0.8 damp:1.0 width:0.5 level:0.5
Change reverb room size (i.e the reverb time) in the range [0 to 1.0] (default: 0.2)
Change reverb damping in the range [0.0 to 1.0] (default: 0.0)
- When 0.0, no damping.
- Between 0.0 and 1.0, higher frequencies have less reverb time than lower frequencies.
- When 1.0, all frequencies are damped even if room size is at maximum value.
Change reverb width in the range [0.0 to 100.0] (default: 0.5)
num value defines how much the right channel output is separated of the left channel output.
- When 0.0, there is no separation (i.e the output is mono).
- When 100.0, the stereo effect is maximum.
Change reverb output level in the range [0.0 to 1.0] (default: 0.9)
Turn the chorus on or off
Use n delay lines (default 3)
Set output level of each chorus line to num
Set mod speed of chorus to num (Hz)
Set chorus modulation depth to num (ms)
Reloads the default MIDI routing rules (input channels are mapped 1:1 to the synth)
Deletes all MIDI routing rules.
Starts a new routing rule for events of the given type.
router_chan min max mul add
Limits the rule for events on min <= chan <= max. If the channel falls into the window, it is multiplied by \u2019mul\u2019, then 'add' is added.
router_par1 min max mul add
Limits parameter 1 (for example note number in a note events). Similar to router_chan.
router_par2 min max mul add
Limits parameter 2 (for example velocity in a note event). Similar to router_chan.
Finishes the current rule and adds it to the router.
router_chan 0 7 0 15
Will accept only note events from the lower 8 MIDI channels. Regardless of the channel, the synthesizer plays the note on ch 15 (synthchannel=midichannel*0+15).
router_chan 0 7 0 15
router_par1 1 1 0 64
Configures the modulation wheel to act as sustain pedal (transforms CC 1 to CC 64 on the lower 8 MIDI channels, routes to ch 15).
LADSPA must be enabled for these commands to work (-o synth.ladspa.active=1)
Resets LADSPA effect unit to bypass state
ladspa_add lib plugin n1 <\- p1 n2 -> p2 \u2026
Loads and connects LADSPA plugin
Starts LADSPA effect unit
ladspa_declnode node value
Declares control node `node' with value 'value'
ladspa_setnode node value
Assigns 'value' to 'node'
Joshua "Element" Green
Please check the AUTHORS and THANKS files for all credits
SoundFont is a registered trademark of E-mu Systems, Inc.