Table of Contents
AC100 sound mixer
These netbooks use ALC5632 audio codec plus mixer IC which has quite some amount of knobs and switches. Most of them are available for direct manipulation with
GNOME Volume Control and other applications that interact with ALSA mixers.
Analog Audio Mixer Path
Fear not, here's the diagram from the datasheet that allows one to make sense out of all those confusing opportunities:
Understanding it doesn't require any special knowledge, here's a short legend:
DACis Digital to Analog Converter,
DACsmodule gets digital stereo signal via
I2Sbus from the CPU and the
VoiceDACmodule gets mono signal from a digital microphone (placed somewhere inside near the webcam)
ADCdoes the reverse and can be used to convert sound from inputs to digital form which is then sent over
I2Sto the CPU
- A triangle on the diagram means a sound amplifier
- A square marked
Volis an attenuator that a user can tweak to reduce the volume of the signal
- A square with
Mis a mute switch
- A circle with sigma is a module that mixes all the inputs together
- A trapezoid is a mux, a module that allows the user to select only one of the inputs to be connected to the output
Common usage scenarious
Here ALSA control names are used, if you're using alsamixer or other similar software you will not see “Playback” or “Mux” in the control names, that is normal.
Stereo playback on integrated speakers
Should be enabled:
DACL2HP Playback Switch
DACR2HP Playback Switch
Should be set:
SpeakerOut N Muxto
Master and speaker playbacks should be unmuted and set to the desired level.
Proper mono sound via MONO mixer or Speaker mixer is impossible to produce on unmodified hardware, see reversed_polarity_of_one_of_the_integrated_speakers for details. Luckily most usage scenarios do not require that anyway. You can swap polarity of connection of one of the speakers but then
RN/-R would need to be used for the stereo output.