例えばHikakinTV
youtube-dl -x --no-check-certificate --audio-format mp3 -citw -v https://www.youtube.com/channel/UCZf__ehlCEBPop-_sldpBUQ
ちなみにある動画だけであれば
youtube-dl.exe -x --no-check-certificate --audio-format mp3 https://www.youtube.com/watch?v=LrxsE-tbR48
参考サイト
https://qiita.com/gotta_dive_into_python/items/253a55f3dcfeeef2b640
https://askubuntu.com/questions/856911/using-youtube-dl-to-download-entire-youtube-channel?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa