Encode MP3 correctly
If the audio files are saved in MP3 format, signals inaudible to humans are cut off. We will tell you how to encode MP3 correctly to achieve the best possible quality.
What is MP3
To optimally encode an MP3, it is important to have an idea of how MP3 works:
MP3 is an audio codec developed by the Fraunhofer Institute, in particular Karlheinz Brandenburg, for the MPEG I standard.
MP3 is a compression method that Psychoakustig uses: The audio signal is divided into narrow frequency bands. Spectral components that humans hear partially or completely are stored with less precision.
The lower the specified bit rate, the more inaccurate the mapping, and the more likely frequencies above the masking threshold are also stored imprecisely.
Encodes MP3 optimally
Depending on whether you extract music from a CD, voice recordings, or analog media recordings, those records would be encoded, they are partly different settings. Others always make sense. You can do all the settings, for example, in XMedia Recode, which CHIP Online offers for free.
In general, it makes sense to keep the sample rate of the file to be encoded. With audio CD, this is 44100Hz. For recordings on discs or cassettes, 32000Hz is sufficient, speech is still clearly understandable even at 22050Hz.
For pure voice recordings, mono is sufficient; for music, joint stereo is usually more efficient than single stereo, as some bits can be saved losslessly through mid-side encoding.
As a bit rate mode, VBR-ABR (Variable Bit Rate – Average Bit Rate) is always the method of choice: in regions where frequency ranges are clearly masked or where there is absolute silence, an extremely large amount of data is saved that makes sense elsewhere. It can be used. Depending on the type of signal, an MP3 with an average VBA-ABR bit rate of 128 kbps can be significantly more accurate than a constant bit rate (kBR) file of 160 kbps. In any case, with the same file size, it is always at least as good as a KBR file with the same bitrate.
To take advantage of this potential, you should set the VBR quality to the maximum, the minimum bit rate to 32 kbps, and the maximum to 224.
Depending on the nuances of your music, an average bit rate of 128 to 192 kbps is usually ideal. Of course, mono files only need half the bit rate. For speech, 32 to 48 are sufficient for comprehension, up to 64 kbps for slightly clearer sound. Here you can also use a high pass of about 90 Hz.
Of course, you will get the best quality if you set the quality to “high”. Encoding takes a bit longer, but with current processor performance this is not significant.
It is completely useless to encode an MP3 with better quality later or to save a mono file in stereo.
