Setting up a Multitrack Audio Recording Studio

Ever since Elvis plopped down his nickel and crooned a song captured in glistening black vinyl, children everywhere have dreamed of making the next hit single. Unfortunately, doing so usually costs more than the paltry sum The King laid out for his tracks. Today, anyone with a PC can be the next George Martin or Trent Reznor, making the next big hit to be traded illegally, right in their own bedroom! Linux's capabilities make it perfect for multimedia production, and as distributions become easier to install and set up, more ordinary users will want to do more multimedia projects.

To begin, start with your favorite Linux distribution, it doesn't matter which one. I choose Slackware. For this article I will assume you have the sound working and X running on x86 architecture. I'll also assume you know how to navigate Linux and install programs, although you don't have to be a guru. Because this article is targeted toward users who want to make good recordings, there will be less emphasis on the technical aspects of using Linux and more on recording theory and practices, including program-specific HOWTOs.

The two programs I discuss are Gmurf and Broadcast 2000, the latter of which had a nice introductory article in the January 2001 issue of Linux Journal. Neither program requires root privileges to install or run, and both are easy to install and run (just follow the documentation), so I won't cover that here.

The only other things you'll need aren't computer-related at all and consist of noise-making items (such as your voice or a pan and spoon), studio gear (such as a 48-channel powered mixing board with DSP or a Wah-Wah pedal) and a mic or three.

Once you have everything you think you need (trust me, you'll want more stuff once you get going), the next step is to record. Multitrack recording is essential for getting the best possible sound out of more than one instrument, and it is necessary if you are the only one playing the instruments.

Multitrack recording, in its simplest form, is simply multiple single tracks recorded and played in synch, so that the resulting music sounds like one composition. An audio CD is a multitrack recording consisting of two tracks that are played through a machine that sends one track to the left speaker and one to the right.

Music studios traditionally have tape machines that can record up to 64 tracks, and multiple machines can be synched to make an unlimited amount of tracks available. Then each track can have effects added to it and be mixed down to a regular stereo recording for placement on a CD, cassette or web site. With Linux, you can have an all-digital studio, with the number of tracks limited only by the space on your hard drive.

The two basic formats that we'll be working with are .wav and Broadcast's hypertext audio language (HTAL). Gmurf and Broadcast 2000 both work with .wav files; while Gmurf will actually let you edit and manipulate the bits of data that make up a sound file, Broadcast 2000 works only with pointers to various parts of sound files. The result is a small project file, one that leaves no fear of accidentally chopping the middle out of that killer take, and one that makes it incredibly easy to add "just one more" track.

The two quickest and cleanest ways of getting audio onto your computer are to rip from a pre-existing CD or download samples from the Web. The first method has the advantage of offering an enormous selection of samples to choose from, acquired simply and easily with countless CD-ripping utilities for Linux. However, current law limits the duration of samples you are legally allowed to use, and you'll need to be creative in finding even small samples that would be appropriate to use in an original composition. The second method has the advantage of being an easy way to get usable instrument sounds presampled. This is a great thing if you are looking for a unique instrument or any instrument to which you do not have access. I use downloaded samples to create drum tracks for lack of a real drum machine or drum kit.

The major disadvantage to using prerecorded sounds is that you will need some kind of sequencer to get maximum benefit and flexibility from the samples. For example, it is easy to arrange drum samples in Broadcast 2000 to create a great-sounding beat, but there is no easy way to add swing to the track to make a really funky groove, aside from tweaking it by trial and error.

Making a live recording using a microphone through your sound card will give your opus the "you are there" energy that can make a good tune rock. Synthesized noises are okay for backgrounds, but if you want your creation to turn out sounding more like a person played it and less like a midi-enabled web site, you'll have to break out some real recording tools.

Some programs will allow you to make a stereo recording on your hard drive, using the input jacks on your sound card. Broadcast 2000 is no exception, and shortly I'll discuss exactly how to record that screaming guitar solo quicker than you can say "real recording studio".