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The SoLoud::Monotone is a replayer for MONOTONE tracker songs. MONOTONE is a pc-speaker tracker, available on GitHub at

The SoLoud MONOTONE replayer can play MONOTONE v1 songs (only format available at the time of this writing). You can pick the number of "hardware" voices used - typically the songs are composed for a single voice (PC beeper).

The default waveform used is square wave, but other waveforms are also supported.


You can clear all data from the Monotone object using clear:

void clear();

This is primarily used internally.


You tell monotone to load a file with the load function:

result load(const char *aFilename); 

If loading fails, the function returns an error code.

SoLoud::Monotone swingin1;


The loadFile() can be used to load audio from a SoLoud::File object. This is useful for integrating with virtual filesystems / packfiles, such as PhysFS.


Alternate way of loading the file is to read from a memory buffer.

result loadMem(unsigned char *aMem, int aLength, 
               bool aCopy, bool aTakeOwnership);

The aTakeOwnership parameter can be used to tell SoLoud to free the pointer once it's done with it. The aCopy parameter is here for compatibility with the other loadMem functions.


The setParams() function can be used to adjust the way SoLoud plays the MONOTONE file.

result setParams(int aHardwareChannels, int aWaveform);

Most songs are composed for a single hardware channel. SoLoud supports up to 12 hardware channels (more can be easily added by editing soloud_monotone.cpp)

The supported waveforms include:

Waveform Description
WAVE_SQUARE Raw, harsh square wave
WAVE_SAW Raw, harsh saw wave
WAVE_SIN Sine wave
WAVE_TRIANGLE Triangle wave
WAVE_BOUNCE Bounce, i.e, abs(sin())
WAVE_JAWS Quater sine wave, rest of period quiet
WAVE_HUMPS Half sine wave, rest of period quiet
WAVE_FSQUARE "Fourier" square wave; less noisy
WAVE_FSAW "Fourier" saw wave; less noisy


Adjusting the looping of a monotone sound does not currently have any effect. All music is set to loop by default.


As with any other audio source, you can attach filters to monotone audio sources.

gMusic.setFilter(0, &gLofi);


You can stop all instances of a monotone sound source with stop(). This is equivalent of calling soloud.stopAudioSource() with the sound source.



Set the inaudible behavior of the sound. By default, if a sound is inaudible, it's paused, and will resume when it becomes audible again. With this function you can tell SoLoud to either kill the sound if it becomes inaudible, or to keep ticking the sound even if it's inaudible.

// Keep on talking even if I'm not around
gSpeech.setInaudibleBehavior(true, false);


Set the default volume of the instances created from this audio source.


Monotone.setLoopPoint(), Monotone.getLoopPoint()

If looping is enabled, the loop point is, by default, the start of the stream. The loop point can be changed, and current loop point can be queried with these functions.

double t = snd.getLoopPoint();
snd.setLoopPoint(t + 1); // skip 1 second more when looping
snd.setLoopPoint(0); // loop from start

Inherited 3d audio interfaces

Like all other audio sources, monotone inherits the 3d audio interfaces. Please refer to the 3d audio chapter for details on:

Copyright©2013-2020 Jari Komppa