Use this to download this category as MP3 with youtube-dl:
declare -a list=("https://www.youtube.com/channel/UCNsyUg9n7TB365g4n13UOIg/videos" "https://www.youtube.com/channel/UC8Ux-LOyEXeioYQ4LFzpBXw" "https://www.youtube.com/channel/UC-2EkisRV8h9KsHpslQ1gXA" "https://www.youtube.com/channel/UC_KidpuCqhbvqZedgq2DPpA/videos" "https://www.youtube.com/channel/UC7H198GlIEz9GQt8sLLcWdw" "https://www.youtube.com/channel/UC8ZFaiEUQEdZyZkMQ4gcXLQ" "https://www.youtube.com/channel/UCAFQjCZo5okIPkHUQlBZM-g")
for val in ${list[@]}; do
name=$(basename "$val")
if [ -e $name ]
then
continue
fi
mkdir $name
cd $name
youtube-dl -f mp3-128 $val
cd ..
done
