Use this to download this category as MP3 with youtube-dl:
declare -a list=("https://www.youtube.com/channel/UCPFChjpOgkUqckj3378jt5w" "https://www.youtube.com/user/dexsilicium/" "https://www.youtube.com/user/greatscottlab/" "https://www.youtube.com/channel/UCVqx3vXNghSqUcVg2nmegYA/" "https://www.youtube.com/channel/UCe3v5cVACw-5BKQOcwUaM8w/videos" "https://www.youtube.com/channel/UCjiVhIvGmRZixSzupD0sS9Q/" "https://www.youtube.com/user/thonain/" "https://www.youtube.com/user/IHPU0/" "https://www.youtube.com/user/jipihorn/" "https://www.youtube.com/user/eaterbc/" "https://www.youtube.com/user/electronupdate/videos" "https://www.youtube.com/user/EugeneKhutoryansky/videos" "https://www.youtube.com/channel/UC8uT9cgJorJPWu7ITLGo9Ww" "https://www.youtube.com/channel/UCfOrKQtC1tDfGf_fFVb8pYw/videos" "https://www.youtube.com/channel/UCUCo_G9HneFK4Luncw6v-Bw/videos")
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