There are several categories of music software. But the lines between the categories are blurring, even as we work. In the last fifteen years or so, three main types of computer music software have been developed.

Audio Multitrack Software

Audio multitrack software attempts to re-create a multitrack recording and playback studio inside your computer. When recording software was first introduced, massive PCI cards and other hardware were needed to help the computer cope with all of the audio data. A good example is the professional Pro Tools audio software that still relies on PCI or PCI-E cards for computer power. Nowadays, software that deals exclusively with audio and not MIDI is very difficult to find, because most, if not all, studio software incorporates MIDI in some regard. But if you look hard enough, you might find some free or very cheap software on the Internet that deals with just audio.

MIDI Sequencing Applications

Before computer-based audio was even a dream, there was MIDI, which consists of small text commands to control the playing of synthesizers. Computers started to work with MIDI data around twenty-five years ago. A MIDI sequencer lets you record and manipulate many tracks of MIDI information, allowing the computer to play back long, complicated parts that might be unplayable by a single person. Editing and manipulation is possible on even the minutest of levels. You can create piano parts that are faster than anyone can play or program an entire orchestra to play back your music.

MIDI was the reason that the computer made its first appearance in the recording studio. Even today, you can still get MIDI-only sequencing programs. Some of the more famous programs that were the pillars of the MIDI sequencing world, such as Logic and Cubase, have grown up to include sophisticated audio features as well. So just like audio-only applications, it's hard to find just MIDI; most are integrated.

Integrated MIDI and Audio

Today, most recording software integrates MIDI with audio. As all of the programs grew up, an all-in-one solution became necessary. The software suites that dealt strictly with audio, such as Pro Tools, eventually adopted MIDI. Conversely, the MIDI-only camp grew audio wings. All the programs covered in this chapter allow you to record and edit MIDI and audio together in the same program. With audio programs, not only can you play and record, but you can process effects and perform exacting editing, which is what makes these programs special. On the audio side, nonlinear editing is the distinguishing factor that makes the computer more than just an emulation of a multitrack recorder. What's nonlinear editing? Read on!

What Nonlinear Editing Means to You

Let's start with linear editing. Think of a CD. Suppose you were recording a mix for your car's CD player. Later on you decide you'd prefer the track you placed first on the CD to be at the end of the CD. You would have to burn an entire new CD to rearrange the order of tracks. There is no way to just magically “move” that song. You can't do this because a CD is linear—it's read in a line and whatever appears first will be played first and so on.

Computer audio systems don't rely on linear data storage; instead they use hard drives that can read and write data in a nonlinear fashion. Although we hear this data as music, the computer processes and stores it like any other data, and that works in our favor. Audio data is stored on the hard disk in a nonlinear manner, which allows you to change the order of tracks and move whole sections of your song with ease. This is one of the main reasons computer audio took off. Editing is far superior on a computer system. It's easy to imagine that audio on a computer is processed much like text in a word processor—you're free to cut, copy, and paste as you wish. Audio data is treated the same way, and that's nothing short of revolutionary!

Audio-Editing Applications

Historically, the first audio recording on a computer was not multitrack audio but simply stereo files. These files were loaded into an audio-editing application that allowed nonlinear editing in high resolution. After the edits were completed, they were sent back to the tape they came from. This was the beginning. Even as multitrack grew up, audio-editing applications were still popular ways to edit in high detail. Nowadays, audio-editing programs like Wavelab are used for mastering and remastering because they don't deal with multitrack or mixing data, only the final stereo file. For many, audio-editing applications like these are the last step before burning or CD duplication. These programs are also handy if you work on a portable digital recorder and wish to transfer the final stereo output into the computer for editing and burning to CD.

Proprietary Audio Systems

Proprietary audio systems are audio software and hardware packaged together under a brand name and sold for use on a computer. Pro Tools LE is an example of such a system and is, in fact, one of the only proprietary systems on the market today that can be used in the home studio.

Unlike Pro Tools, almost all audio software and hardware systems are modular, meaning you can buy software and audio interfaces from different companies and they will work together. For example, you don't have to use Digital Performer with a MOTU interface just because they are made by the same company. So too, you can get standard drivers that allow you to use almost any piece of software with almost any piece of hardware, regardless of the manufacturer.

Pro Tools, as mentioned previously, is a proprietary system of hardware and software that works together on your home computer. Pro Tools M-Powered is designed for specific M-Audio hardware. Because the software is tied to the hardware, it's a self-contained system. This means you can't run Pro Tools LE or M-Powered software with any other hardware than what is supported, but you can use Pro Tools hardware with other applications. This is not a bad thing if you love Pro Tools and wish to spend all your time working with it. Many people get confused by this and think they can plug their sound card into Pro Tools.