Audio Production in Gnu/Linux

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Editor's Note: Audio Production in Linux
Oct 23, 2009, 23 :02 UTC by Carla Schroder
Managing Editor

Audio recording and editing with computers is still in its infancy, and is full of pitfalls. Just figuring out what hardware to use is enough to drive a person to drink. But once you get it all figured out and get everything working, it's fun and powerful.

There are boatloads of great Linux software for every imaginable recording, editing, and special effects task. Finding Linux-compatible recording interfaces is rather vexatious, though don't feel picked-on because many audio hardware vendors don't even write decent Windows drivers. The easiest PC audio production platform is Mac OS X. It has its own share of glitches and hassles, but in my experience you're up and running pretty quickly.



Using Windows highlights just how deficient the poor thing is. Windows XP SP3 is by far the best Windows for audio production, which is not saying much. Audio recording and editing can be very resource-intensive; dual-core CPUs and lots of RAM are good to have. (Though it depends what you're doing; making podcasts and recording interviews can be done on low-spec machines like netbooks, and older PCs and notebooks.) You need a mighty beast just to have enough power for Vista to get out of its own way, and Windows 7 is only marginally better. Vendors are still slow to release Vista drivers let alone Windows 7.



Linux has its own hassles; simple one- and two-track recording is easy and doesn't need any special hacks. You can make satisfactory podcasts on most any stock Linux distribution. But for high-quality multitrack recording and editing you want a low-latency kernel and well-supported audio hardware, and that can lead to some serious hair-pulling trying to make it work. The easiest way is to use a special distro like 64Studio, Ubuntu Studio, the Planet CCRMA packages for Fedora, or dyne:bolic. These have everything you need including tweaked kernels, so all you need is supported audio hardware.



Don't use PulseAudio, aRts, or ESD. Use ALSA all by itself, or ALSA plus JACK, the excellent low-latency sound server and router.
One- and Two-Track Recording

Two-track recording is the easiest in Linux; it's not very resource-intensive, and there are a lot of affordable recording interfaces to choose from. I like USB 1.1 recording interfaces. Find one that is class-compliant so you don't need any silly special drivers and it should just work. All manner of devices use USB these days: microphones, turntables, mixers, preamps, and analog-digital/digital-analog converters.

Some examples of USB 1.1 devices that work well in Linux are Behringer's Xenyx USB mixers, the M-Audio MobilePre, and the M-Audio FastTrack Pro.



Visit the ALSA SoundCard Matrix to see more supported audio interfaces. The Linux Audio Users Mailing List is a great place to find current information and help.
Multitrack Recording

USB 2.0 in theory should be a wonderful boon to Linux audio, allowing low-latency multitrack recording and plug-n-play devices, but unfortunately it seems the entire audio industry lost its collective mind, and instead of making class-compliant devices chose to go the hard way of writing special proprietary Mac and Windows drivers. Stupidity? Corruption? Who can say, but the next time some dimwit tries to tell me that supporting Linux is too hard I'm going to twap them with a USB 2.0 spec book.

There are a number of good PCI and PCMCIA recording interfaces that work well in Linux. These are less flexible than USB and sometimes they will pick up internal noise and interference. The M-Audio Delta PCI cards are famous for working well in Linux, and have been around long enough to support a healthy second-hand market. RME Hammerfall makes high-end expensive audio interfaces, and a number of them work great with Linux.



Firewire is the ultimate in multitrack recording, and thanks to the FFADO project there are some good supported devices, and lots more on the way. (See the supported devices page.)



Using Firewire recording interfaces in Linux means getting JACK working, and possibly doing some custom compiling to get everything working correctly. Some distros are not very careful with their build options or making sure the related applications are up-to-date and compatible. I use 64Studio 3.x beta and so far so good, though a friend of mine uses Planet CCRMA on Fedora 10 and it looks even better. It's stable and he has suffered few glitches.



I am waiting most eagerly for a Focusrite Saffire Pro 26 that I ordered earlier this week. It has everything that I want: eight microphone preamps, phantom power, and expansion via all manner of external devices. Focusrite is supportive of the FFADO project so they get my hard-earned clams.



One thing to beware when you're shopping for external recording interfaces is they like to boast of having skillions of plugins. But they may not be the types of plugins you want. For example, it's common to see numbers like 16 and 24 I/O, but then they have only two mic preamps and the rest are midi, SPDIF, ADAT, MIDI, line, or instrument ports. I need lots of mic preamps and line/instrument ports; the rest, no.



Stay tuned for further Linux audio production adventures, hopefully happy ones!
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