It seems that the 1.12 version had compressed music files that were significantly smaller than the ones that are currently in 1.19 (which were taken directly from the original mod's files), it might be worth it to use the 1.12 files instead for the sake of smaller file size as long as there isn't noticeable difference in quality.

Notably, the Aether Tune disc was almost 3 times smaller, being under 1MB in 1.12.