youtube audio download code example

Example 1: youtube mp4 downloader

I suggest videovor.com, it's really great and you even get an option to choose
if you want the whole video or just the audio!

Example 2: youtube to mp4

ytmp3.cc is the best by far

Example 3: youtube-dl download audio

youtube-dl -F http://www.youtube.com/watch?v={video ID}  to get available audio
then
youtube-dl -f {number of available audio} http://www.youtube.com/watch?v={video ID}