Volume Normalization / Adjustment

Audio Surgeon has the ability to calculate the volume or loudness of an audio file or song. Beyond this basic calculation, AS has the ability to modify or change this volume, either up or down. When you adjust the volume of a group of audio files to have the same value, that is called volume normalization. The accuracy by which this is done is an important consideration.

Below is a small study comparing a product called MP3 Gain to Audio Surgeon. In this study a small group of 80 songs were chosen at random from a music library and ran on both products to normalize the volume to 95.0 dB. MP3 gain wins when looking only at processing time. For a group of 80 songs MP3 gain took about 1.5 minutes to normalize over 80 tracks, Audio Surgeon took 11 minutes. However, where AS excels, is in achieving a close proximity to the target volume. As the table below shows, in AS’s case, 88% of the track levels were within 0.2 dB of the target. MP3Gain, on the other hand, only landed 33% of the results within 0.2 dB. AS allowed very few tracks (8) to exceed the target, and this by only 0.1 dB. MP3Gain allowed 44% of all tracks to exceed the target level.

This accuracy is very important because small changes, especially those that exceed the target range can potentially cause files to clip, which previously did not.

Comparison of Volume Change Results
AS vs. MP3Gain
Target Volume 95dB
Volume (dB) AS MP3Gain
94.300
94.406
94.422
94.649
94.742
94.8143
94.979
95.0433
95.185
95.206
95.303
95.405
95.505
95.605
95.707
Within 2 dB
or Target
88%33%
% Above
Target
10%44%

The ability to determine loudness or volume and to change it, along with Tempo and Key Determination are three of the unique features of songs that can be calculated by Audio Surgeon. There is a good overview video of Audio Surgeon found on our home page, if you’d like to learn more. If you are interested in buying, or if you’d like to take our fully functional free demo for a test drive, please click the appropriate blue button near the top, right side of this page.