If I hear a mob in Minecraft, how far away could it be?

I've done some testing, and it seems that it is 16 blocks, from the mob's head to yours. I tested by encasing a pig with dirt, but I assume that it's the same for all mobs. Except Ghasts, that is. It's definitely longer there, probably 100 blocks.

BTW, yes, the pig is perfectly fine except for the time I accidentally hit him, and the time that he got shot by a skeleton.

I have confirmed by putting a lot of zombies and skeletons in one hole, that the maximum hearable distance as of Minecraft 1.18 for those mobs is exactly 16 blocks from the center of the mob indeed.

By spawning a non-moving ghast (/summon minecraft:ghast ~ ~ ~ {NoAI:1}) I also found that the exact distance for them is 80 blocks.

What's worth noting is that the hearable zone is a sphere with a radius of 16, and not a cube.

I confirmed that this is correct by using the in-game subtitles feature, that shows a subtitle even for the most silent sounds.