MP3: Sampling rate

December 2016


MP3: Sampling rate



Does a 320Kbps MP3 file has really a 320Kbps sampling rate? Not always, it all depends on the initial encoding!

Example:
Take the case of a .mp3 audio file initially encoded at 128 kbps, now re-encode it with a sampling rate of 320kps using a software like Audacity. The weight of the file will be heavier and it will be identified as being a 320kbs file, but it won't deliver the same audio quality!
The conversion of an audio file (.wav) to MP3 involves removing parts (less audible) the track and there are no software that can rebuild them ..

NB: when recording or exporting a file with an audio editor, you can choose to between several sampling rates 64kbs, 96kbs, 128kbs, 320 Kbs...

How to check the sampling frequency

Don't forget to check the frequency rate (in Hz).


To avoid losing too much quality when converting a 320Kbps file to 128Kbps, keep the original frequency!
The sampling rate is based on the frequency:
Sampling frequencies (Hz)Rate (Kb/s)
48000 320, 256, 224, 192, 160, 128, 96, 64, 32
44100 320, 256, 224, 192, 160, 128, 96, 64, 32
22050 320, 256, 224, 192, 160, 128, 96, 64, 32
11025 320, 256, 224, 192, 160, 128, 96, 64, 32

Conversion: loss in quality

Each conversion will result in a loss of quality, as your music files are being entirely re-encoded during the process.
Even when converting a 128Kbps file to 128Kbps, it will lose in quality!

Related :

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