Audio sinks and sources: Advanced Gtk+ Sequencer Audio Reference Manual

Audio sinks and sources

AgsDevout — Output to soundcard
AgsDevin — Input from soundcard
AgsMidiin — Input from sequencer
AgsFifoout — Output to pipe
AgsJackServer — JACK instance
AgsJackClient — JACK connection
AgsJackPort — JACK resource.
AgsJackDevin — Input from soundcard
AgsJackDevout — Output to soundcard
AgsJackMidiin — Input from sequencer
AgsPulseServer — pulseaudio instance
AgsPulseClient — pulseaudio connection
AgsPulsePort — pulseaudio resource.
AgsPulseDevin — Input from soundcard
AgsPulseDevout — Output to soundcard
AgsCoreAudioServer — core audio instance
AgsCoreAudioClient — core audio connection
AgsCoreAudioPort — core audio resource.
AgsCoreAudioDevin — Output to soundcard
AgsCoreAudioDevout — Output to soundcard
AgsCoreAudioMidiin — Input from sequencer

Here are objects listed to interact your sound devices using ALSA, JACK, Pulseaudio or CoreAudio.