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# apt install lame # wget http://val.bmstu.ru/unix/Media/Knockin_on_Heavens_Door.mp3
# lame --decode Knockin_on_Heavens_Door.mp3 # sox -V Knockin_on_Heavens_Door.wav -r 8000 -c 1 Knockin_on_Heavens_Door.raw
# sox -t al -r 8000 -c 1 /usr/share/asterisk/sounds/recordings/speech.alaw speech.wav # ffmpeg -nostats -loglevel 0 -i speech.wav -acodec libvorbis speech.ogg
# lame --preset voice -v -B 64 -a XYZ.wav XYZ.mp3