The handling of Mp3, Mp4, FLAC, Ogg, APE, AAC and Wav files can be divided into 2 types: distorting and not distorting. And if distorting ways of processing change an original relation of the amplitudes of their level and frequency, the not distorting ways of processing change level of all amplitudes equally or leave invariable level of all amplitudes and frequencies of sound.
The most widespread distorting way of processing is the use of an equalizer, and the most widespread not distorting way of processing is to use the normalizer. In this article we will look at normalizer.
The point of normalization is that the amplitude changes the original audio signal and the shape remains the same.
And it feel on hearing as change of force a sound or volume.
Changing the volume is accompanied by a change in the dynamic range, ie the ratio of the loudest value to the most silent value of beep.
With the increase of the volume increases, and dynamic range.
The restriction, reduction in dynamic range and volume is accompanied by the fact that the music sounds exactly, monotonously, all the while about the same volume, it becomes boring, inexpressive, more flat, expression and dynamism disappears, brightness of perception is lost.
Of course, you can use a volume control or the volume button and simply increase the volume, without the help of a normalizer but if you do not have one song, but a group of songs, or songs, it gives a tangible inconvenience. Each composition has its own volume, dynamic range and average volume.
If all the songs or musical compositions are executed in one style or a genre that, as a rule, we can restrict peak normalization. Peak normalization for group of compositions fixes for each composition volume, the dynamic range at the same level so that all compositions have the same dynamic range or volume.
If all the songs or musical compositions are executed in different style or a genre that, as a rule, resort to normalization on an average level. Normalization on an average level for group of compositions fixes the volume or dynamic range at different levels for each composition depending on the average value of the volume of this composition that creates sensation of identical volume at transition from one song or a composition to another for the group of compositions.
Let's consider normalization of a sound with reference to program Sound Normalizer.
Unlike sound editors such as "Sound Forge", which normalize files Mp3, first convert the Mp3 file to a Wav file, then normalize the Wav file and then convert it back to a file Wav to Mp3. Sound Normalizer fulfills normalization of files Mp3 without conversions or any transformation and thus simply changes a control footing in each frame of Mp3 file.
Also, in contrast to such players as the "foobar 2000", which normalize Mp3 files using APEv2 tags while leaving each frame Mp3 file untouched - Sound Normalizer does not use APEv2 tags for normalization, which makes it possible to listen to Mp3 files with the changed volume in the hardware players with flash memory. Besides Sound Normalizer fulfills testing and normalization on each channel separately that allows to align automatically at normalization volume level in each channel on identical level that improve a stereo effect.
In single-player mode to open the file, run the command "Open".
You can go in the batch mode having executed a command "Batch Processor".
You can open files in the Batch Processor using three ways:
Add
If you use the command "Add Files" that can select Mp3, Mp4, FLAC, Ogg, APE, AAC and Wav file or files;
If you use the command "Add Folder" that can select all Mp3, Mp4, FLAC, Ogg, APE, AAC and Wav files in this folder;
If you use the command "Add Folders" that can select all Mp3, Mp4, FLAC, Ogg, APE, AAC and Wav files in this folder and all subfolders contained in that folder.
The program for Mp3 files normalization on an average level with definition of clipping. Because after compression Mp3 files often sound level is close to the peak level or exceeds that one peak normalization for Mp3 files it appears inappropriate.
The best option would be a combination of normalization on an average level with a peak normalization preventing a clipping.
A clipping appears in Mp3 file when Wav file is converting with peak level above 90 %. Perform peak normalisation therefore before converting Wav files in Mp3 for Wav files with peak level no more than 90%.
Clipping is a distortion of the audio signal, which is expressed in the appearance of "hissing" and "crackle".
Please listen and look at the same beep without clipping and with clipping.
No Clipping (the file NoClipping.mp3)
Listen and compare the non-clipped audio "NoClipping.mp3" with the clipped audio "Clipping.mp3"
No Clipping
Clipping
Sound Normalizer
Sound Normalizer
Clipping (the file Clipping.mp3)
Listen and compare the clipped audio "Clipping.mp3" with the non-clipped audio "NoClipping.mp3"
Clipping
No Clipping
Sound Normalizer
Sound Normalizer
For Mp3, Mp4, FLAC, Ogg, APE, AAC and Wav files both single and batch mode to normalization on an average level it is advisable to check and determine the recommended maximum level of normalization without clipping.
Test
The recommended maximum level of normalization without clipping - is the optimum level of normalization eliminating clipping and providing maximum sound quality.
In batch mode the recommended maximum level of batch normalization of the list of processing without clipping - is the optimum level of normalization eliminating clipping and providing maximum sound quality, which is calculated for a current list processing.
Batch Test
In batch mode, there is a command "Normalize each file on a maximum level without clipping" - This is an implementation of peak normalization on a maximum level for Mp3 files, ie in each file volume increased just enough as the speaker does not "rattle" and the volume of the maximum possible. In this case the normalization tends to 0 decibels (DB).
The "Save the ratio between the channels" is disabled by default and Sound Normalizer automatically adjust according to the average peak level or the volume of each channel. When this command Sound Normalizer will retain the original ratio of the previous volume level between the channels by increasing the volume of each channel to the same value to the level of a given synchronized sliders control normalization. That is, the command "Save the ratio between the channels" allows you to change the volume of the two stereo channels (left, right) to the same value, and thus retains its original volume differences between channels. In this two-channel stereo signal is selected having the maximum amplitude or loudness. Based on this information and the normalization is performed simultaneously in the two channels.
Level of normalization for Mp3 files expresses in percentage concerning value in 89 db in the program Sound Normalizer. That is 89 db - it is 100%.
89 dB - is defined by practical consideration for majority Mp3 files volume level, on which else there are no clipping.
Reducing the size of Mp3, Wav and FLAC files
If you want to reduce the quality and size of the mp3 file, then you need to use the converter or converter from mp3 to mp3.
Sound Normalizer includes a converter from mp3 to mp3 with the preservation of the original ID3 v1 and v2 tag (Artist / Title / Genre and so on.).
It should be noted that the increase in the flow rate or bit rate mp3 files does not increase the sound quality of the file.
Turning in a batch mode as shown in the figure below, you will see the column "Estimated size" value in this column will be updated every time you are in the encoder settings (button "Settings ..." Output format "MP3" in the "Batch Converting") press the "Apply" button or "OK".
Estimated size
For reduce size mp3 file is better to reduce stream speed or bitrate. In this case you have 3 variants of a compression mode of the stream data:
1. With constant stream speed (Constant bitrate, CBR);
2. With variable stream speed (Variable bitrate, VBR);
3. With average stream speed (Average bitrate, ABR).
CBR mode will give you predicted size mp3 file.
VBR mode will give you unpredictable a value of reduction mp3 file.
ABR mode will give you predicted with much bigger (in comparison with VBR) accuracy a value of reduction mp3 file.
Once you have transferred the sound file format FLAC you using Sound Normalizer can reduce the file size .flac at least another 10%. To do this you need to open the file .flac and reduce the level of normalization of the file based on the fact that the decrease in the level of normalization by 1% reduces the file size .flac at least 0.2%.
Findings
Normalization - is not distorting type of treatment.
The normalization is accompanied by change in volume or dynamic range, that is the relation of the loudest value to the most silent value of beep.
The normalization allows to improve quality: If the Mp4, FLAC, Ogg, APE, AAC, Wav files, this translates into an increase in dynamic range for Mp3 files it expresses by elimination of a clipping.
Starting normalization Mp3, Mp4, FLAC, Ogg, APE, AAC and Wav files must be kept in mind that there are 2 sorts of normalization:
Peak normalization;
Normalization on an average level.
You should know that there are 2 modes of normalization:
The single;
The batch.
The Batch normalizing works with a list of processing and allows to align perceived volume for group of compositions. If the group tracks all the songs belong to the same genre or style of music, it is usually enough and peak normalization.
If the group compositions are songs belonging to different genres, it is usually necessary to use normalization on an average level.
For Mp3 files must be used for the normalization of the average level, since their volume is usually equal to or exceeds the maximum, which causes clipping. In addition, because of its small size on disk or flash memory is a large number of Mp3 files, which often belong to different genres of music. Therefore, for Mp3 files is the optimal use of normalization on an average level together with peak normalization preventing a clipping and allowing to receive maximize quality.
