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Better than the others, just lemixx

 

LEMIXX's stream

 

 

About our audio format:

 


Why 32khz is ideal for streaming, it's our explanation:

  • The uncompressed audio bit rate is:
    32.0x16x2 - 1.024 Mbit/s  (audio is filtered at 16Khz, 32/2).
    44.1x16x2 - 1,4112 Mbit/s  (audio is filtered at 22Khz, 44/2).

PCM Audio bit rate calculation is: Sampling rate in Khz X Bit depth x 2 (stereo)

 

We can say for mp3 audio streaming 32Khz is better because listners can't hear above 16khz anyway.
Listener's audio chain also can't reproduce higher frequencies and specialy with mp3 codecs.


Human is sensitive to audio compression artefacts like low bit rate mp3 encoding or codecs cascading,
generating phase error for example and much more complicated things....

 

So why to encode above 16khz ? it's better to reduce the PCM bit rate before encoding

here is the demonstration why with the compression ratio:

 

  • Streaming at 160kbits like lemixx:
    EX@32k: 1024/160 - the compression ratio is 6.4 to 1. (lemixx choice)
    Ex@44.1K: 1411,2/160 - the compression ratio is 8.82 to 1.
  • Exemple with regular 128Kbit/s at 44.1Khz:
    1411.2/128 - the compression ratio is 11 to 1.

 

The ratio compression should be the minimum as possible, so we can say
160kbit/s at 32Khz is almost 2 times better than 128kbit/s 44.1Khz !!


We are here just talking about compression not about lemixx's audio processing chain.

 

To compare, do not forget your prefered FM station has a filter set to 15khz.
(worldwide FM limitation for stereo gen), so we are still better !

 

We can go deeper with codec profiles, audio processing...perhaps later!

 

All the day, all the night, you can hear the music play, lemixx.com

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