Sunday, June 05, 2022

Emacspeak: The Complete Audio Desktop Under Pulseaudio

Emacspeak: The Complete Audio Desktop Under Pulseaudio

1. Executive Summary

Porting Emacspeak sound environment to Pulseaudio.

Until now, emacspeak features that enhance the auditory display have relied exclusively on ALSA and avoided Pulseaudio all together. As Pulseaudio improves, and simultaneously gets harder to get rid of, I recently ported the required features to work under Pulseaudio, see below for details.

2. Summary Of Auditory Display Enhancements

  • Notifications, e.g., speaking the time, incoming IM messages

etc. are spoken on a separate notification stream.

  • The above normally plays on the right ear, but enhanced with a binaural effect.
  • This can be configured to be on the left ear when running Emacspeak remotely on a cloud-top.
  • A Bauer Stereo To Binaural (BS2B) filter is applied to all output streams to provide an enhanced headphones listening experience.
  • The outloud server has been updated to request lower latency from Pulse; Pulseaudio defaults are too high for highly responsive TTS.

For details on Emacspeak's enhancement to the auditory display, see prior articles listed in the References section.

3. Configuring Pulseaudio To Enhance The Auditory Display

All of these features have been available until now by installing a custom .asoundrc; these are now available under Pulseaudio by installing a .config/pulse/ in the user's home directory.

cp EMACSPEAK_DIR/etc/pulse/ ~/.config/pulse; pulseaudio -k

The above is a one-time operation that sets up the audio environment — see etc/pulse/

Date: 2022-06-05 Sun 00:00

Author: T.V Raman

Created: 2022-06-05 Sun 09:16