Convert between AFF and raw file formats.
Use a specific extension (default: `aff`)
afconvert -a extension path/to/input_file path/to/output_file1 path/to/output_file2 ...
Use a specific compression level (default: `7`)
afconvert -X0..7 path/to/input_file path/to/output_file1 path/to/output_file2 ...