Environmental Effects¶

For the sake of brevity, we only document the constraints of each effect’s properties. Further details can be found at OpenAL’s Effect Extension Guide which specifies the purpose and usage of each value.

Base Effect¶

class palace.BaseEffect¶

Base effect processor.

Instances of this class has no effect (pun intended).

It takes the output mix of zero or more sources, applies DSP for the desired effect, then adds to the output mix.

This can be used as a context manager that calls destroy upon completion of the block, even if an error occurs.

Parameters: context (Optional[Context], optional) – The context from which the effect is to be created. By default current_context() is used.
Raises: RuntimeError – If there is neither any context specified nor current.

Chorus Effect¶

class palace.ChorusEffect¶

Chorus effect.

The chorus effect essentially replays the input audio accompanied by another slightly delayed version of the signal, creating a “doubling” effect. This was originally intended to emulate the effect of several musicians playing the same notes simultaneously, to create a thicker, more satisfying sound.

Parameters

waveform (str) – Either ‘sine’ or ‘triangle’.
phase (int) – From -180 to 180.
depth (float) – From 0.0 to 1.0.
feedback (float) – From -1.0 to 1.0.
delay (float) – From 0.0 to 0.016.
context (Optional[Context], optional) – The context from which the effect is to be created. By default current_context() is used.

Raises

RuntimeError – If there is neither any context specified nor current.

delay¶: Delay, from 0.0 to 0.016.

depth¶: Depth, from 0.0 to 1.0.

feedback¶: Feedback, from -1.0 to 1.0.

phase¶: Phase, from -180 to 180.

waveform¶: Waveform, either ‘sine’ or ‘triangle’.

Reverb Effect¶

palace.reverb_preset_names: Tuple[str, …]¶: Names of predefined reverb effect presets in lexicographical order.

class palace.ReverbEffect¶

Environmental reverberation effect.

Parameters

preset (str, optional) – The initial preset to start with, falling back to GENERIC.
context (Optional[Context], optional) – The context from which the effect is to be created. By default current_context() is used.

Raises

ValueError – If the specified preset cannot be found in reverb_preset_names.
RuntimeError – If there is neither any context specified nor current.

air_absorption_gain_hf¶: High frequency air absorption gain, from 0.892 to 1.0.

decay_hf_limit¶: Whether to limit high frequency decay.

decay_hf_ratio¶: High frequency decay ratio, from 0.1 to 20.0.

decay_lf_ratio¶: Low frequency decay ratio, from 0.1 to 20.0.

decay_time¶: Decay time, from 0.1 to 20.0.

density¶: Density, from 0.0 to 1.0.

diffusion¶: Diffusion, from 0.0 to 1.0.

echo_depth¶: Echo depth, from 0.0 to 1.0.

echo_time¶: Echo time, from 0.075 to 0.25.

gain¶: Gain, from 0.0 to 1.0.

gain_hf¶: High frequency gain, from 0.0 to 1.0.

gain_lf¶: Low frequency gain, from 0.0 to 1.0.

hf_reference¶: High frequency reference, from 1000.0 to 20000.0.

late_reverb_delay¶: Late reverb delay, from 0.0 to 0.1.

late_reverb_gain¶: Late reverb gain, from 0.0 to 10.0.

late_reverb_pan¶: Late reverb as 3D vector of magnitude between 0 and 1.

lf_reference¶: Low frequency reference, from 20.0 to 1000.0.

modulation_depth¶: Modulation depth, from 0.0 to 1.0.

modulation_time¶: Modulation time, from 0.004 to 4.0.

reflections_delay¶: Reflections delay, from 0.0 to 0.3.

reflections_gain¶: Reflections gain, from 0.0 to 3.16.

reflections_pan¶: Reflections as 3D vector of magnitude between 0 and 1.

room_rolloff_factor¶: Room rolloff factor, from 0.0 to 10.0.

property send_auto¶: Whether to automatically adjust send slot gains.