help understanding architecture of audio

[Andrew Farris]

don fisher wrote:
> I am quite familiar with connecting arbitrarily complex audio systems. I 
> have been trying to understand how the sections of the linux audio plug 
> together.
> 
> For sources I have a microphone, audio and video CDs, and MP3s. For 
> output I have an audio jack, a bluetooth transmitter.
> 
> Is there a mux (or preamp equivalent) that allows one to select and 
> input and output path? Perhaps also set the gain, balance, base, treble 
> and loudness.

Pulseaudio has interface controls to handle nearly anything you want to do with 
a stream.  You need to find and install all the pulse tools like paman, 
pavumeter, pavucontrol, and padevchooser.

> Is there a document that describes haw to turn on, and then access the 
> various input and and output channels.

As mentioned in other email, docs on gstreamer, alsa, or pulseaudio are where 
you want to look really.  There are other sound subsystems but these are where 
the real forward movement is in linux audio.

I'm no expert either, but generally applications implement calls to the 
gstreamer libraries, the alsa sound subsystem is either used above that (i.e. 
pulseaudio is not being used and alsa configuration is all there is), or 
pulseaudio is used in combination with alsa with PA being the top-level 
interface/system.  F9+ use pulseaudio running as a user daemon, interfacing with 
alsa controlling the hardware devices, with applications streaming sound in 
through gstreamer or direct alsa channels.

-- 
Andrew Farris <lordmorgul at gmail.com> www.lordmorgul.net
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