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apx_ctl
Control an Acoustic Processing Extension (APX) module

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apx_ctl

Control an Acoustic Processing Extension (APX) module

Note:

This utility can only be used if you have QNX Acoustic Management Platform 3.0 installed.

Syntax:

apx_ctl [options]

Runs on:

QNX Neutrino

Options:

-a apx

The Acoustic Processing Extension (APX) module to start or issue a command to. You can specify apx in the following ways:

[card_num:]dev_num — card number and device number. The default for both the card number and the device number is 0.
name — APX card name (e.g., pcmPreferredp, pcmCxDyp).

-e chns:volume_chn0:...:volume_chnN

Set volume of external amplifiers (outside of io-audio system).

-t dataset

Load the specified runtime acoustic processing dataset.

-u user_volume

Override the default user volume with the system output volume.

-x id:channel[:data]

Set or get data on an APX module for parameters of size int16_t. where:

id is the ID of the parameter
channel the acoustics channel the parameter is for
data is the data for the parameter (when setting only)

Description:

The apx_ctl utility controls an Acoustic Processing Extension (APX) module. If you specify just the -a option, apx_ctl starts the APX.

See the apx_ctl.c appendix for the source for this utility in the Audio Developer's Guide.

Page updated: March 12, 2026