I believe the theory was that because the headphones/earbuds send energy directly into your ear canal (while external sounds bounce off more stuff and travel fu

I believe the theory was that because the headphones/earbuds send energy directly into your ear canal (while external sounds bounce off more stuff and travel further), that it is more harmful (over prolonged periods of time). I don’t know how volume correlates with sound pressure, intensity and power, so I can’t comment on whether or not that’s true. Note that this was for prolonged (many hours) of listening, even at low volume. With that said, I googled and came up blank looking for these studies, so you could be right. Without the studies to back it up, what I wrote is kinda meaningless.