How to specify Vorbis encoding options using `sox`?

Question

I want to record audio encoded using Vorbis quality level 6, but how to pass the encode options to rec?

Answer 1

From the soxformat(7) man page:

SoX can decode all types of Ogg Vorbis files, and can encode at different compression levels/qualities given as a number from -1 (highest compression/lowest quality) to 10 (lowest compression, highest quality). By default the encoding quality level is 3 (which gives an encoded rate of approx. 112kbps), but this can be changed using the -C option (see above) with a number from -1 to 10; fractional numbers (e.g. 3.6) are also allowed.