音訊只搜集 cc0 或是沒有任何版權，也就是連需要姓名標示的也不收集
https://www.youtube.com/channel/UCorqI2EE1avwlTCekjfi0LQ
https://musopen.org/ We provide recordings, sheet music, and textbooks to the public for free, without copyright restrictions. Put simply, our mission is to set music free.
https://freesound.org/browse/tags/?f=tag:%22music%22 選擇有cc0標示的