Synthesizer settingsaudio-channelsint11128
By default, the synthesizer outputs a single stereo signal. Using this option, the synthesizer can output multichannel audio. Sets the number of stereo channel pairs. So 1 is actually 2 channels (a stereo pair).audio-groupsint11128
Normally the same value as synth.audio-channels. LADSPA effects subsystem can use this value though, in which case it may differ.chorus.activebool1 (TRUE)
When set to 1 (TRUE) the chorus effects module is activated. Otherwise, no chorus will be added to the output signal. Note that the amount of signal sent to the chorus module depends on the "chorus send" generator defined in the SoundFont.chorus.depthnum8021
Specifies the modulation depth of the chorus.chorus.levelnum2010
Specifies the output amplitude of the chorus signal.chorus.nrint3099
Sets the voice count of the chorus.chorus.speednum0.30.295
Sets the modulation speed in Hz.cpu-coresint11256
(Experimental) Sets the number of synthesis CPU cores. If set to a value greater than 1, then additional synthesis threads will be created to take advantage of a multi CPU or CPU core system. This has the affect of utilizing more of the total CPU for voices or decreasing render times when synthesizing audio to a file.default-soundfontstrC:\soundfonts\default.sf2 (Windows),
${CMAKE_INSTALL_PREFIX}/share/soundfonts/default.sf2 (all others)
The default soundfont file to use by the fluidsynth executable. The default value can be overridden during compilation time by setting the DEFAULT_SOUNDFONT cmake variable.device-idint00126
Device identifier used for SYSEX commands, such as MIDI Tuning Standard commands. Only those SYSEX commands destined for this ID or to all devices will be acted upon.dynamic-sample-loadingbool0 (FALSE)
When set to 1 (TRUE), samples are loaded to and unloaded from memory
on demand.
effects-channelsint222Currently unused.gainnum0.20.010.0The gain is applied to the final or master output of the synthesizer. It is set to a low value by default to avoid the saturation of the output when many notes are played.ladspa.activebool0 (FALSE)
When set to "yes" the LADSPA subsystem will be enabled. This subsystem allows to load and interconnect LADSPA plug-ins. The output of the synthesizer is processed by the LADSPA subsystem. Note that the synthesizer has to be compiled with LADSPA support. More information about the LADSPA subsystem later.lock-memorybool1 (TRUE)
Page-lock memory that contains audio sample data, if true.midi-channelsint1616256
This setting defines the number of MIDI channels of the synthesizer. The MIDI standard defines 16 channels, so MIDI hardware is limited to this number. Internally FluidSynth can use more channels which can be mapped to different MIDI sources.midi-bank-selectstrgsgm, gs, xg, mma
This setting defines how the synthesizer interprets Bank Select messages.
gm: ignores CC0 and CC32 messages.
gs: (default) CC0 becomes the bank number, CC32 is ignored.
xg: CC32 becomes the bank number, CC0 toggles between melodic or drum channel.
mma: bank is calculated as CC0*128+CC32.
min-note-lengthint10065535
Sets the minimum note duration in milliseconds. This ensures that really short duration note events, such as percussion notes, have a better chance of sounding as intended. Set to 0 to disable this feature.overflow.agenum1000-1000010000
This score is divided by the number of seconds this voice has been
active and is added to the overflow priority. It is usually a positive
value and gives voices which have just been started a higher priority,
making them less likely to be killed in an overflow situation.
overflow.importantnum5000-5000050000
This score is added to voices on channels marked with the
synth.overflow.important-channels setting.
overflow.important-channelsstr""
This setting is a comma-separated list of MIDI channel numbers that should
be treated as "important" by the overflow calculation, adding the score
set by synth.overflow.important to each voice on those channels. It can
be used to make voices on particular MIDI channels
less likely (synth.overflow.important > 0) or more likely
(synth.overflow.important < 0) to be killed in an overflow situation. Channel
numbers are 1-based, so the first MIDI channel is number 1.
overflow.percussionnum4000-1000010000
Sets the overflow priority score added to voices on a percussion
channel. This is usually a positive score, to give percussion voices
a higher priority and less chance of being killed in an overflow
situation.
overflow.releasednum-2000-1000010000
Sets the overflow priority score added to voices that have already
received a note-off event. This is usually a negative score, to give released
voices a lower priority so that they are killed first in an overflow
situation.
overflow.sustainednum-1000-1000010000
Sets the overflow priority score added to voices that are currently
sustained. With the default value, sustained voices are considered less
important and are more likely to be killed in an overflow situation.
overflow.volumenum500-1000010000
Sets the overflow priority score added to voices based on their current
volume. The voice volume is normalized to a value between 0 and 1 and
multiplied with this setting. So voices with maximum volume get added
the full score, voices with only half that volume get added half of this
score.
polyphonyint256165535
The polyphony defines how many voices can be played in parallel. A note event produces one or more voices. Its good to set this to a value which the system can handle and will thus limit FluidSynth's CPU usage. When FluidSynth runs out of voices it will begin terminating lower priority voices for new note events.reverb.activebool1 (TRUE)
When set to 1 (TRUE) the reverb effects module is activated. Otherwise, no reverb will be added to the output signal. Note that the amount of signal sent to the reverb module depends on the "reverb send" generator defined in the SoundFont.
reverb.dampnum001
Sets the amount of reverb damping.reverb.levelnum0.901
Sets the reverb output amplitude.reverb.room-sizenum0.201
Sets the room size (i.e. amount of wet) reverb.reverb.widthnum0.50100
Sets the stereo spread of the reverb signal.sample-ratenum44100.022050.096000.0
The sample rate of the audio generated by the synthesizer.
threadsafe-apibool1 (TRUE)
Controls whether the synth's public API is protected by a mutex or not. Default is on, turn it off for slightly better performance if you know you're only accessing the synth from one thread only, this could be the case in many embedded use cases for example. Note that libfluidsynth can use many threads by itself (shell is one, midi driver is one, midi player is one etc) so you should usually leave it on.
verbosebool0 (FALSE)
When set to 1 (TRUE) the synthesizer will print out information about the received MIDI events to the stdout. This can be helpful for debugging. This setting cannot be changed after the synthesizer has started.
MIDI driver settingsautoconnectbool0 (FALSE)
If 1 (TRUE), automatically connects FluidSynth to available MIDI input ports. alsa_seq is currently the only driver making use of this.
driverstralsa_seq (Linux),
winmidi (Windows),
jack (Mac OS X)alsa_raw, alsa_seq, coremidi, jack, midishare, oss, winmidiThe MIDI system to be used.realtime-prioint50099Sets the realtime scheduling priority of the MIDI thread (0 disables high priority scheduling). Linux is the only platform which currently makes use of different priority levels. Drivers which use this option: alsa_raw, alsa_seq, ossportnamestrUsed by coremidi and alsa_seq drivers for the portnames registered with the MIDI subsystem.alsa.devicestrdefaultALSA MIDI device to use for RAW ALSA MIDI driver.alsa_seq.devicestrdefaultALSA sequencer device to use for ALSA sequencer driver.alsa_seq.idstrpidID to use when registering ports with the ALSA sequencer driver. If set to "pid" then the ID will be "FLUID Synth (PID)", where PID is the FluidSynth process ID of the audio thread otherwise the provided string will be used in place of PID.coremidi.idstrpidClient ID to use for CoreMIDI driver. 'pid' will use process ID as port of the client name.jack.serverstrJack server to connect to for Jack MIDI driver. If an empty string then the default server will be used.jack.idstrfluidsynth-midiClient ID to use with the Jack MIDI driver. If jack is also used as audio driver and "midi.jack.server" and "audio.jack.server" are equal, this setting will be overridden by "audio.jack.id", because a client cannot have multiple names.oss.devicestr/dev/midiDevice to use for OSS MIDI driver.winmidi.devicestrdefaultDevice for Windows MIDI driver.MIDI player settingsreset-synthbool1 (TRUE)If true, reset the synth before starting a new MIDI song, so the state of a previous song can't affect the new song. Turn it off for seamless looping of a song.timing-sourcestrsamplesample, systemDetermines the timing source of the player sequencer. 'sample' uses the sample clock (how much audio has been output) to sequence events, in which case audio is synchronized with MIDI events. 'system' uses the system clock, audio and MIDI are not synchronized exactly.Shell (command line) settingspromptstr""In dump mode we set the prompt to "". The ui cannot easily handle lines, which don't end with cr. Changing the prompt cannot be done through a command, because the current shell does not handle empty arguments.portnum9800165535The shell can be used in a client/server mode. This setting controls what TCP/IP port the server uses.