Portable Hard Disk Recorder How-To
Three years ago, this project would have been a royal pain in the hind end. Although the Multiface has always been Linux-compatible, once upon a time, doing real-time audio on any hardware required a lot of fancy command-line tricks and kernel recompilation. The plethora of studio distributions in the last couple years has radically changed the process and has brought the most powerful parts of the Linux multimedia subsystem into the reach of people who are power users and hobbyists, rather than remaining in the domain of kernel hackers. Thanks to the power of Linux and open-source software, for the cost of an old laptop and a new audio interface, you own a proper, full-featured, multitrack digital audio field recorder. Go forth, record, edit, create and compress!
Some Problems with Digital Audio
As you go about your recording, you're going to discover some of the limits of digital recording, such as the fact that current technology doesn't allow for sample rates high enough to reproduce cymbals and other sounds with high, clear treble accurately—sounds you won't run into when recording voices, but you will encounter in music and sound effects. To better understand how digital sampling works, and how you can use sound reinforcement and acoustic techniques to overcome some of those limitations, pick up the Yamaha Sound Reinforcement Handbook. It will help you understand how audio reinforcement works and how to compensate for such problems.
Laptop-compatible Pro Audio interface support is spotty and hard to find accurate information on, but an excellent place to start is the FFADO Project at www.ffado.org.
The other place for good information is the ALSA Project hardware database at www.alsa-project.org.
For more information about tweaking the RME Multiface 2, see the HDSP How-To at pd.klingt.org/files/hdsp-howto.html.
Dan Sawyer is the founder of ArtisticWhispers Productions (www.artisticwhispers.com), a small audio/video studio in the San Francisco Bay Area. He has been an enthusiastic advocate for free and open-source software since the late 1990s, when he founded the Blenderwars filmmaking community (www.blenderwars.com). Current projects include the independent SF feature Hunting Kestral and The Sophia Project, a fine-art photography book centering on strong women in myth.
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