I mean, with a a difference of only 9 dollars, I wouldn't expect one to sound all that much better than the other.

to be honest, both $6 and $15 sound crazy cheap for audio equipment. if you've managed to find something that's acceptable while only spending ~20 bucks that's pretty surprising.

Yeah, it's both surprising and unsurprising how cheap good stuff can get nowadays. I was going through a few lists of good budget earbuds for making my choices, in hopes that I could get something better than the regular convenience store earbuds while still within my acceptable price range. And well, I did.