Sound Library Reference
Procedures, command families, examples, and backend notes for FreeBASIC's built-in sound library.
Generated Sound
Description
The sound library, or sfxlib, is the built-in audio layer used by FreeBASIC's new sound commands. It covers generated tones, PLAY-string music, short sound effects, music file playback, MIDI commands, output device selection, and audio capture where the target backend supports it.
Programs that use these commands automatically request the sfxlib runtime. If a program does not use the sound command surface and needs words such as Music, Sfx, or Device as normal identifiers, define Fb_No_Sfxlib before those names are parsed.
How sfxlib is arrangedPrograms that use these commands automatically request the sfxlib runtime. If a program does not use the sound command surface and needs words such as Music, Sfx, or Device as normal identifiers, define Fb_No_Sfxlib before those names are parsed.
Generated sound commands create tones, notes, PLAY strings, waveforms, envelopes, and instruments. The MUSIC family controls one current music stream. The SFX family loads and plays short reusable samples. MIDI sends MIDI commands where a backend supports MIDI. DEVICE selects the output backend, and CAPTURE records input where capture support exists.
For headless tests and package smoke tests, set SFXLIB_DRIVER=null before the program starts to use the null output driver.
Quick exampleFor headless tests and package smoke tests, set SFXLIB_DRIVER=null before the program starts to use the null output driver.
' generated tone
sound 440, 0.25
' PLAY-string phrase
play "t140 o4 cdefgab"
' short reusable sample
sfx load 1, "click.wav"
sfx play 1
Sleep 1000, 1
sound 440, 0.25
' PLAY-string phrase
play "t140 o4 cdefgab"
' short reusable sample
sfx load 1, "click.wav"
sfx play 1
Sleep 1000, 1
Generated Sound
Beep
Digital Audio and MIDIProduces a beep or short pitched note.
SoundPlays a generated tone.
TonePlays a generated tone on a selected channel.
NoisePlays generated noise.
NotePlays a named musical note.
PlayPlays BASIC PLAY strings.
TempoSets or returns PLAY-string tempo.
ChannelSets or returns the default generated-sound channel.
OctaveSets or returns the default note octave.
VoiceSets or returns the default instrument.
VolSets master volume.
VolumeSets or returns master or channel volume.
BalanceSets or returns master stereo balance.
PanSets or returns channel stereo pan.
WaveDefines a generated waveform.
EnvelopeDefines an ADSR envelope.
InstrumentDefines or assigns an instrument.
Music
Devices, Backends, and CaptureLoads, plays, loops, pauses, resumes, stops, and queries the current music stream.
SfxLoads and controls short sound effects by id or channel.
MidiOpens MIDI output, plays MIDI files, and sends MIDI messages where supported.
Device
Lists, selects, and queries sfxlib output devices.
Sfxlib BackendsSummarizes the output backends used on supported targets.
CaptureStarts, pauses, resumes, stops, reads, and saves audio capture where available.
Advanced sfxlib headersDocuments raw PCM output, underrun and sample-rate queries, final-output WAV recording, and whole-mix echo.