SoX
SoX - Sound eXchange is a cross platform command line tool for converting and editing audio files.
Installation in Termux
pkg install sox
Configuration
To enable recording from the microphone add following line in $PREFIX/etc/pulse/default.pa
load-module module-sles-source
Usage
Conversion
sox input.wav output.mp3
Playback
play audio.wav
Recording
rec audio.wav trim 0 00:10
More examples
Normalize an audio file (adjust volume to the maximum peak level, without clipping):
sox --norm input_audiofile output_audiofile
Alternative:
sox input_audiofile output_audiofile norm
The standard bitrate for conversion to mp3 is 64 kbit per channel.