I’m coming late to this, but back in 2006 a couple of audiologists decided to test a bunch of earbuds and headphones to measure how much hearing damage they cause when playing MP3 tracks at a range of volumes, from whisper-quiet to full-on 100%.

That chart above summarizes the results. It’s slightly alarming to me, because I sometimes listen to my Sansa Fuze player — using earbuds — at 80% or 90% of the volume, in part because when I’m walking around Manhattan, the ambient noise is pretty high, so the music has to cut over that. If hese guys are right, I can listen for no more than 1.5 hours, and possibly as little as 22 minutes, “without greatly increasing their risk of hearing loss”. Mind you, who really knows: As the scientists note in their writeup, people’s auditory physiology varies quite a lot.

But there’s also some more, and newer, nifty research from this team — about the listening habits of young people. One public-health-policy concern these days is that young people are listening to music waaaaaay too loud, and are all gonna be deaf by their mid 40s. To figure out whether this was true, these same scientists studied 30 Denver-Boulder-area teenagers.

It turns out things aren’t so bad. Only a small minority of kids — between 7 and 24 per cent — are listening to their MP3 players at eardrum-shredding levels. “We don’t seem to be at an epidemic level for hearing loss from music players,” Portnuff said. What’s more, boys tend to listen to music louder than girls, teenagers tend to listen at quieter levels as they get older, and some teenagers appear to have trouble judging precisely how loud they’re listening.

But dig this …

The study also showed that teen boys listen louder than teen girls, and teens who express the most concern about the risk for and severity of hearing loss from iPods actually play their music at higher levels than their peers, said CU-Boulder audiologist and doctoral candidate Cory Portnuff, who headed up the study. Such behaviors put teens at an increased risk of music-induced hearing loss, he said. [snip]

“We really don’t a have good explanation for why teens concerned about the hearing loss risk actually play their music louder than others,” he said.

Heh. Maybe it’s because they’ve been listening so loud for so long that it’s just begun to unsettle even themselves . Not enough to stop, yet, but enough to start wondering, hmmm, isn’t this gonna make me deaf?