The Advanced Linux Sound Architecture is composed of several parts. The first is a fully modularized sound driver which supports module autoloading, devfs, isapnp autoconfiguration, and gives complete access to analog audio, digital audio, control, mixer, synthesizer, DSP, MIDI, and timer components of audio hardware. It also includes a fully-featured kernel-level sequencer, a full compatibility layer for OSS/Free applications, an object-oriented C library which covers and enhances the ALSA kernel driver functionality for applications (client/server, plugins, PCM sharing/multiplexing, PCM metering, etc.), an interactive configuration program for the driver, and some simple utilities for basic management.
Gemu is a Gnome application designed to configure sound cards based on the EMU10K1 platform from Creative Labs. Gemu is capable of adding, viewing and deleting audio routes, turning on Live Drive IR, turning on the 12db boost to the front/headphone jacks on Live cards, setting the S/PDIF frequency on Audigy cards, setting the recording source, turning on digital passthrough mode, setting to the analog or digital mode of the dual-mode jack of 5.1 cards, adding and seeing patches for sources and destinations, and controlling volume on a per-route basis or by source or destination.
IRMix is an audio mixer application for Linux. It uses the Lirc infra-red receiver system to provide an imitation of a TV's on-screen display, and handles making audio volumes controllable from an infra-red remote control. If your X server supports the Xft extension, Irmix will use it to add a nice translucency effect to the OSD window.
JackMixDesk is based on JackMiniMix and is a general purpose mixer for the Jack Audio Connection Kit. It has an OSC-based control interface, and a configurable number of mono/stereo inputs and pre/post sends/outputs that can be controlled by sending it OSC messages. There is LASH support and an XML config file.