The first step in creating a pro audio setup is to install the proper software necessary to process recordings and other audio data. Although traditionally this software has been expensive, powerful yet free open-source and shareware programs are now available that effectively compete with the features of more famous programs. Two excellent programs of this nature are Audacity and Reaper. Audacity is a full-featured wave editor for mastering a final mix or editing individual audio clips for inclusion in a mix. Reaper is a multitrack audio-mixing program with robust features that even many expensive programs do not offer. Both programs are available as a free download.
Special hardware may be necessary if you plan to do your own recording with a computer. Some pro audio work does not involve computer recording. External recording devices such as DAT or Flash-based recording systems capture the audio on location. In these cases, any computer can mix and master the audio after it is transferred into the computer using a standard USB cable. However, using a multitrack audio-recording program in real time to capture audio requires hardware more capable than the included sound cards on consumer PCs. Expect to spend a couple hundred dollars, at least, on a good sound card that offers true audio inputs, including quarter-inch cable connectors.
The technique used to mix the audio in a program is the same regardless of the program used. All the software options lay out a stacked track window where each audio piece is layered onto another. Getting the audio into the program and moving around the pieces to construct a mix is straightforward, but careless mixes are easy to create.
Learning to create a quality sound mix requires careful attention to the nuances of each audio track and a continuous eye on the level meters. Digital audio must be kept under the 0 db marker on all tracks and the final output mix. Even the slightest push above 0 creates digital distortion.
When the final mix is exported from the program as a single WAV file, then the mastering begins in a program such as Audacity. Although the music may contain both loud and quiet segments, it must be mastered to output at a similar volume level throughout so listeners are not constantly adjusting their volume dials. Use a compressor feature or plug-in in the mastering program to create a more uniform volume for the final mix.