Normalizing an Audio Track

If an audio file seems quiet compared to others at the same volume, normalization may be necessary. In the following screen shot, an example of a file requiring normalization is presented.

This file is not utilizing the available dynamic range. The "0" on the left of the screen shot equals no volume and the + or - "1" represents maximum volume. Therefore, this sound is a little less than half volume.

The "normalize" command, found in most professional audio software, searches the entire file for its maximum peak. It then places the peak at the maximum of the available dynamic range and moves the rest of the file respectively. The result is a louder audio file. If the software determines the maximum peak is already utilizing the full dynamic range, the file will not be altered.

Typically, this is a "destructive" command as it permanently alters the original file with the new volume. Some software packages utilize a "non-destructive" version of the command. This same examination of the audio file occurs; however, the result is achieved by a respective volume increase within the software. The original file is not altered.

In MOTU's Digital Performer, the Normalize command is a destructive one. Do not worry, in most cases, a normalized file is desirable. Normalize every file you plan to add to a compact disc. A compact disc containing normalized files allows the listener to enjoy the material without having to use excessive volume with the playback device. Increased volume often leads to the addition of system noise to the listening experience.

To normalize an audio file in Digital Performer, enter the Soundbites window (shift-b.) Select the audio file by clicking on it once.

Next, click the Edit button at the top of the Soundbites window. This will make the audio's waveform visible. Use the mouse or the "Select All" command (cmd-a) to select the entire audio waveform.

Go to the Audio menu and select Normalize. Based on the size of the audio file, the processing time will vary. Upon completion, the audio file's waveform will change, and the file will be permanently altered.

To export the newly altered sound file out of Digital Performer, visit my instuctions on "Bouncing".

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All screen shots © Mark of the Unicorn