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How to improve quality of the MP3 and Wav - files?

Ways of processing of the MP3 and Wav - files can be divided into 2 look conditionally: distorting and not distorting. And if the distorting ways of processing change the original ratio and level of amplitudes and frequencies of a sound then which are not distorting ways of processing change the level of all amplitudes equally or leave invariable the level of all amplitudes and frequencies of a sound.

The most widespread distorting way of processing is the equalizer, and the most widespread not distorting way of processing is the normalizer. In this article we will consider a normalizer .

The essence of normalization is that amplitude of an initial sound signal changes, and the form remains former. And it is felt aurally as change of sound intensity or loudness.

Change of loudness is followed by change of dynamic range, that is a ratio of the loudest value to the most silent value of a sound signal. With increase in loudness also dynamic range increases.

Narrowing and reduction of dynamic range is followed by the fact that music sounds exactly, monotonously, all the time with approximately identical loudness, it becomes boring, inexpressive, more flat, the expression and dynamism vanishes, perception brightness is lost.

Of course, it is possible to use the handle or the button of loudness and just to increase its level, without resorting to the help of a normalizer, but if you have not one composition, but the whole group of compositions or songs, then it gives a notable inconvenience. At each composition the dynamic range and the average level of loudness.

If all musical compositions are executed in one style or a genre, then, as a rule, it is possible to be limited to peak normalization . Peak normalization for group of compositions fixes for each composition dynamic range at one level in such a way that all compositions have the same dynamic range.

If all musical compositions are executed in different style or a genre, then, as a rule, resort to normalization on the average level . Normalization on the average level for group of compositions fixes dynamic range at the different level for each composition depending on average value of loudness of this composition that creates feeling of identical loudness upon transition from one composition to another for all group of compositions.

Let`s consider normalization of a sound in relation to Sound Normalizer program .

Before starting normalization, you need to open the file. 2 modes are provided in the program: single and package.

In single the mode to open the file, execute the " command; To Open . For transition to package the mode to you needs to execute the " command; Package " processor;.

In the Package processor it is possible to open files in three ways .

If you execute the " command; To Add the " files; you will be able to choose the MP3 or Wav - the file or files.

If you execute the " command; To Add the " folder; you will be able to choose all as the MP3 or Wav - the files which are in this folder.

If you execute the " command; To Add the " folder; you will be able to choose all as the MP3 or Wav - the files which are in this folder and in all subfolders which are in this folder. by

In the program for the MP3 - files realized normalization on the average level with definition of cuts. As after compression for the MP3 - files quite often the level of a sound appears near peak level or exceeds it, one peak normalization for the MP3 - files is inexpedient.

The normalization combination on the average level to the peak normalization preventing cuts of a sound signal will be the most optimal variant.

Cuts of a sound signal are called still klippingy is the distortion of a sound signal which is expressed in emergence hissings and cod .

For Wav - files only peak normalization is still provided in the Sound Normalizer program.

For the MP3 - files both in single, and in batch mode before normalization it is expedient to execute check and to define the recommended maximum level of normalization without cuts.

The recommended maximum level of normalization without cuts is the optimum level of normalization eliminating cuts and providing the maximum quality of a sound.

In batch mode the recommended maximum level of package normalization of the list of processing without cuts is the optimum level of normalization eliminating cuts and providing the maximum quality of a sound, counted for the current list of processing.

In batch mode there is a " team; To Normalize each file on a maximum level without cuts . It represents realization of peak normalization on a maximum level for the MP3 - files.

Normalization level for the MP3 - files is expressed in the Sound Normalizer program as a percentage concerning value in 89 DB. That is, 89 DB are 100%.

89 DB are the Mp3 defined by practical consideration for the majority - files the loudness level at which still there are no cuts.

Summary . Normalization is a not distorting type of processing. It is followed by change of loudness or dynamic range, that is the ratio of the loudest value to the most silent value of a sound signal changes.

Normalization allows to improve quality: if for Wav - files it is expressed in increase in dynamic range, then for the MP3 - files it is expressed in elimination of cuts.

Starting normalization of the MP3 and Wav - files, it must be kept in mind that there are two types of normalization: peak normalization; normalization on the average level. And two modes of normalization: single and package.

Batch mode of normalization works with the list of processing and allows to level the perceived loudness for group of compositions. If in group of compositions all songs belong to the same genre or style of music, then there is usually enough also peak normalization. If in group of compositions there are songs belonging to different genres, then it is usually necessary to use normalization on the average level.

For Wav - files in most cases have enough also peak normalization as quite often the level of their loudness is not equal maximum and the group of the lost Wav - files on a disk of usual capacity, as a rule, belongs to one genre.

For Mp3 - files needs to use normalization on the average level as their level of loudness is, as a rule, equal to maximum or exceeds it that causes emergence of cuts. Besides from - for the small size on a disk of usual capacity a large number of the MP3 - files which quite often belong to different genres of music settles down. Therefore for them there will be optimum use of normalization on the average level together with the peak normalization preventing cuts of a sound signal and allowing to receive the maximum quality.