ALSA User Info
The Linux Audio Users Guide provides a quick reference point to many useful documents, tutorials, links and a professional support database for Linux audio.
ALSA MIDI/sequencer tutorial http://www.djcj.org/LAU/webcount/link.php?id=midisynth_howto&url=http://linux-sound.org/quick-toots/4-sequencers_and_softsynths/quick-toot-midisynth_howto.html English, Spanish
The ALSA utils are a collection of small and often extremely powerful applications designed to allow users to control the various parts of the ALSA system. The alsactl app is a way to save settings for your device. The amixer app is a command line app which allows adjustments to be made to a devices volume and sound controls. The alsamixer app is an ncurses version of amixer. The acconnect and aseqview apps are for making MIDI connections and viewing the list of connected ports. The aplay/arecord apps are for commandline playback and recording of a number of file types including raw, wave and aiff at all the sample rates, bitdepths and channel counts known to the ALSA library.
There are a number of apps in the ALSA tools package. They range from envy24control which provides complete control over all devices with an envy24 chip, to firmware loaders for pcmcia, USB and the hdsp devices. There is also the hdspmixer app which is a carbon copy of the totalmix app for windows and mac platforms. To use them you need to build and install them seperately. Make sure you read the README and INSTALL files for usage instructions.