On May 31, 2014, at 3:27 PM, catsoul wrote: > Anyone know how to gauge safe listening levels using headphones and any OS X computer? > > is “halfway” on an iMac same as “halfway” on any other mac? I can't tell you, and I suspect that things are different for different headphones because they all don't have the same sensitivity. It's likely different for different age Macs too (they likely have varying amplification power), and it's probably different even among different Mac models. I do know that Apple was once sued by someone who claimed that they suffered hearing loss because Apple's iPod headphones had too high a maximum volume. Apple lost that case: http://www.forbes.com/2006/02/02/jobs-apple-ipod-cx_cn_0202autofacescan05.html But the ruling was overturned on appeal: http://www.cnet.com/news/apple-wins-appeal-in-earbud-hearing-loss-lawsuit/ Nevertheless, as a result of that case, Apple now limits the maximum volume that their headphones can attain. How that compares to other computers and headphones, I don't know. ___________________________________________ Randy B. Singer Co-author of The Macintosh Bible (4th, 5th, and 6th editions) Macintosh OS X Routine Maintenance http://www.macattorney.com/ts.html ___________________________________________