Linux: It Sounds Good to Me
Greetings to all readers of the Linux Journal Web site, and welcome to the first installment of a new monthly column about Linux audio software. For those of you who have been following developments in the Linux audio world, it should come as no surprise that a column such as this one has arrived. But for those of you who are thinking “Linux audio? What in the world could that be about?”, you'll find the answers here.
Before starting this month's article, I want to take a moment and introduce myself. I've been using Linux since late 1995, I'm the maintainer of the Linux Sound and Music Software pages on the Web, and I'm the author The Book of Linux Music and Sound (published by the No Starch Press). I've also published a few dozen articles on the Web and in hard-copy (all on Linux audio-related topics); I occasionally lecture in the US and Europe; and I'm currently involved with documentation for the AGNULA project (more about that later). I'm also a professional musician (guitarist/singer/composer), performing and teaching in and around my home of Findlay, Ohio, in the US. When I'm not working in any of those activities, I usually can be found in the company of my beloved Ivy Maria, doing things like cooking, watching movies, practicing Italian or taking walks in the northwest Ohio countryside. Oh, and I'm an avid t'ai chi player and amateur Latinist.
Okay, on to the reasons for this column. I intend to report on various activities and developments in the rapidly evolving world of Linux audio. To most normal users perhaps the term audio software simply means programs to play MP3 and Ogg files or applications that necessarily have something to do with audio, such as CD and DVD players. Although I'll certainly write about such software, I'll also present views of work being done in such fields as MIDI software, telephony, network audio, digital DJing, professional sound recording and many others. I hope you enjoy the column, and I invite all readers to write to me with comments and suggestions.
Out of all my involvements with Linux audio, perhaps my greatest source of pride is to have been a founding member of the Linux Audio Development group. I should make it very clear to my readers that I'm no coder: I have an amateur's knowledge of C, Lisp and Tcl/Tk, but I've never written a substantial audio application, nor do I plan to. However, since my first days in Linux I've been in direct contact with developers of such applications, often in the combined roles of bug-hunter and beta-tester. Since 1996 I've made the acquaintance of almost every developer working on Linux audio software. In 1998, a group of developers and users decided to declare themselves the official Linux Audio Development (LAD) group. At that time the group included about a dozen members, but by December 2003 the group's membership list has grown to more than 600 participants and lurkers.
So what do LAD people discuss ? Well, in its Aims and Ideas section, the original charter states:
The Linux Audio Developers (LAD) list is dedicated to sound architecture and application development for the Linux operating system. With its proven stability and scalability, it is a perfect foundation for the handling and processing of large amounts of audio data. Our goal is to encourage widespread code re-use and cooperation, and to provide a common forum for all audio related software projects and an exchange point for a number of other special-interest mailing lists.
A list such as LAD necessarily maintains a rather high technical bias, but I must emphasize that it is open to anyone who wishes to subscribe and contribute. Some LAD members are among the most significant developers of Linux audio software, including Paul Davis (Ardour, JACK), Kai Vehmanen (ecasound), Fernando Pablo Lopez-Lezcano (PlanetCCRMA), Richard Bown and Chris Cannam (Rosegarden), Werner Schweer (MusE) and many others. You'll meet some of them and learn more about their projects during the existence of this column. I also must note that although the levels of discussion often are quite high, the participants are cordial and friendly--though they can bite back if bitten. It is to be expected on such a list that strong differences of opinion occasionally appear, but it is a testament to the participants' dedication to the goals of LAD that any serious ad hominem attacks or flame-fests are diffused quickly.
Incidentally, the LAD charter also states that most driver-related discussions and hardware installation questions are not within the scope of the mail list. See the LAD home site (listed below) for directions to more appropriate forums.
To give you some idea of what is talked about on the LAD list, here's a sampling of topics from November 2003 traffic:
Details of Matched, a guitar preamp LADSPA plugin from Tim Goetze
A discussion regarding kernel security patches for easier access to SCHED_FIFO/mlockall
News about cross-toolkit programming for host/plugin GUIs
Test results of running Demolition on LADSPA plugins
Does Native Instruments run their Traktor filesystem on Linux through WINE?
An open letter regarding GPL violations in certain audio software for OS/X
A proposition for polyphonic use of LADSPA plugins
Linux audio and the PPC
State of GUIs for modular synths
OSS driver/support for JACK
“Retro” speech synthesis
Singing speech synthesis with Festival
Discussion of Slashdot's report on the Lionstracs Linux-based music keyboard workstation
An exchange of views regarding SkaleTracker, commercialism and the general state of Linux audio software
Using JACK for control voltage (CV) signals
Juicy stuff, to be sure, and typical of the postings for any given month. By the way, as you can see there is constant and varied discussion regarding LADSPA (the Linux Audio Developers Simple Plugin API) and JACK (the JACK Audio Connection Kit), two of the most important community development projects for Linux audio. I'll be covering both in later articles, but you can learn more about them on your own by consulting the Resources at the end of this column.
So, that's a little bit about LAD. Whether you're a seasoned developer looking for an entrance point into the world of Linux audio programming or a complete newbie to programming anything in Linux, the LAD list is an excellent forum for your involvement.
In the natural course of such things, the original LAD list eventually became a bit overcrowded with developers discussing the technicalities of their various projects and users who needed more non-technical advice and encouragement. After some discussion it was decided to split off a new group; thus was born the Linux Audio Users (LAU) group. Obviously this group is targeted at the normal user of Linux audio software, as a look at some of last month's topics indicates:
Notes on the SBLive with Live Drive
The low-latency kernel on Mandrake
Reducing noisy recording/playback
Using a Shure SM57 microphone with a low-end soundcard
Advice on burning audio CDs
Notes on using the Zaurus palmtop for music and sound
Using the M-Audio Quattro USB interface with JACK
MIDI timing problems
Using Stompboxes2 with Audacity
Working with SpiralSynthModular's JACK plugin
Problems using JACK with SuSE
News regarding JACK and KDE/aRts
Problems using VST plugins under Linux
Recommendations for hardware for Linux audio
Advice on stretching sounds
As you can see, the discussions on LAU are focused on presenting and resolving user-land problems with Linux audio applications. Message types also include exclamations of joy/pain over available (or unavailable) software, as well as general questions regarding kernel preparation and distribution-specific issues. As on the LAD list, discussion usually is civil and on-topic, although strong statements and opinions are not absent here either. I recommend joining the LAU list to any users who have a need for a decent audio system under Linux, whether for composing, editing or simply playing your music.
Before I leave this month's topic, I want to mention yet another split from the LAD/LAU lists. Announcements for new and upgraded Linux audio software have a list of their own, the Linux Audio Announce (LAA) list. This list is more narrowly focused than LAD and LAU, existing simply as a handy forum for project announcements. Posts to this list often and sometimes annoyingly are cross-posted to LAD and LAU, but hopefully it will become the preferred list for letting the public know about new and updated releases.
Finally, I want to give special thanks to the efforts of Jorn Nettingsmeier, Benno Sennoner, and Patrick Shirkey. Jorn acts as the chief cook and housekeeper for the LAD/LAU/LAA mail lists, Benno provides the hosting site and Patrick maintains the outstanding Linux Audio Users Guide (also found on Benno's site). You guys rock!
Okay, that's it for this month's column. Next month I'll present my impressions of some of the Linux audio distributions now available, such as AGNULA/Demudi and PlanetCCRMA. Until then, keep making those joyful noises.
Linux Audio Development (LAD): www.linuxdj.com/audio/lad/
Linux Audio Users (LAU): www.linuxdj.com/audio/lad/subscribelau.php3/
The Linux Audio Announce (LAA) mailing list: www.linuxdj.com/audio/lad/subscribelaa.php3/
The Linux Audio Users Guide: www.djcj.org/LAU/guide/index.php
Dave Phillips is a musician, teacher and writer living in Findlay, Ohio. He has been an active member of the Linux audio community since his first contact with Linux in 1995. He is the author of The Book of Linux Music & Sound, as well as numerous articles in Linux Journal.