Some time ago, Mandriva decided to install the PulseAudio sound server by default in its distribution. Personally I did not really like the decision to activate PulseAudio by default in all desktop environments: I have been using Alsa with great satisfaction now for years, and I did not have any problem with that, so having to depend on yet another service did seem overkill to me. Nevertheless, I let PulseAudio be activated on my system too, in order to help as much as possible with bug hunting.

PulseAudio is the new sound server that’s being included in Ubuntu 8.04 and other recent Linux distros. A sound server lets changes be made to sound between the applications and sound hardware layers. Among other features, PulseAudio provides per-application volume controls, a plugin architecture, low-latency, networking features, and good application compatibility.

There are a lot of great sound-related applications for Linux, from basic audio drivers and sound servers to sophisticated mixers, editors, and special effects engines. Which is not much consolation for the user who just wants sound to work on her system, and these days everything old is new again--once again, getting sound to work correctly, or at all, is almost as fun as in the olden days.

One of the great new features in Fedora 8 is the inclusion of the PulseAudio sound server. PulseAudio allows multiple streams of audio to be played at once, eliminating the worry of having your sound card locked up by another running program. There's also a handy volume control applet that will let you set the volume of each audio stream independently. That's right folks, listen to your MP3s, watch (and listen!) to a YouTube video, and voice chat with your IM buddies, all at the same time and with independent control over each program's volume. Setting up PulseAudio is very easy. Read on for instructions.

By default, PulseAudio in Ubuntu up to Jaunty is set to work with 2 speakers (front channels). This tutorial will explain how to enable multiple sound channels (5.1, 7.1, etc) in Pulseaudio.

The sound scheme in Jaunty has some important changes that you need to be aware of. Alsa 1.0.18 and Pulseaudio 0.9.14 are implemented in Jaunty. The new ALSA provides more support and greater functionality for more sound devices than previous versions. Pulseaudio 0.9.14 does some of the same on the sound server side.

PulseAudio is a cross-platform, open source sound server that supports advanced software mixing capabilities and network transparency. PulseAudio is designed to be a drop-in replacement for the Esound daemon and uses a pluggable Esound module for backwards compatibility.

I couldn't get PulseAudio to work on one of my computers no matter what I do. But removing PulseAudio can be tricky and besides, there is a very easy way to "fix" it (if you're using GStreamer as a backend for music and videos). This is very useful for applications which use GStreamer but do not let you select the sound output module like: Rhythmbox, Totem and so on.

PulseAudio is a Linux sound server that, through abstraction layers, promises a myriad of flexible audio features: combining multiple sound cards into a single, multi-channel device, changing output devices on the fly for running applications, even redirecting input and output between machines over the network.