
We often hear someone normalize an mp3 file or a flac, ogg, aac, etc.
Even with the Mp4Gain we talk about normalizing the audio of video files such as Mp4, AVI, mpeg, etc.
What does normalizes mean?
We could say that it refers to something similar to standardize, in the sense that it maintains a volume standard, that it does not lower the loudness up or down, that it stays within a standard, within given limits.
Audio compression
When the music began to digitize, going from analog to digital, it became absolutely necessary to use compressors, which will work as a limiter, to stop the peaks and as an expander or compressor to enhance the valleys of lower loudness.
At the same time, a principle that has to do with the human ear was detected: at higher volume the ear believes that the music is “better heard” and that is where the so-called volume war began.

Each time the audio productions registered an increase in loudness.
All of the above caused anyone who listened to various music files, in an order, to notice differences in the sound of these, which was unpleasant and uncomfortable.
And there arises the need to normalize the volume, to obtain a similar loudness without variations in loudness.
Then we will see that a normalizer is a software or hardware that is responsible for maintaining the loudness of all the audio, because it is not only about music, but we also talk about videos, movies, etc. It maintains that constant sound, without fluctuations.
Even modern normalizers, at least the Mp4Gain, do this by separating the audio by bands, thus achieving an enhancement that the audio had lost when being compressed excessively.
Audio compressors are necessary, but their abuse in the last decades, have managed to reduce the quality of the audio and also that the loudness is not the same between one file and another.
The normalizer has become one of the most important accessories in the audio chain, at least at the user level.
People search everywhere how to equalize volume levels, how to improve volume levels, how to match the volume of their audio files … until they finally find a good normalizer that comes to solve the problem, greatly improving the audio quality and ending the problem of uneven loudness.






