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As users plug into their iPods and iPhones for more hours a day, the choice of headphones is as much about keeping your hearing in top form as it is about sound quality. That's why many are looking at features that let them pump down the volume without sacrificing the sound levels they have come to love.
There is no question that your run-of-the-mill earbuds and over-the-ear headphones have been getting a lot of bad press in terms of their impact on hearing loss. While earphones and headphones don't exactly do your hearing any favors, the real issue around hearing loss is more about the length of exposure.
Trash Talking
"There's no such thing as 'too loud.' It's too loud too long. Things are only damaging to our system if we have a certain exposure over a certain period of time," Brian Fligor, instructor in otology and laryngology at Harvard Medical School, told MacNewsWorld.
Of course, with the wrong headphones, that exposure would be limited indeed. He likens the whole issue to sunburns. "You can be outside without sunscreen and not get a sunburn for the first 10 minutes. With sunblock, it's a longer time before you end up with a problem -- but you will end up with one eventually if you stay out for hours.
"With an iPod, wherever you set the volume will determine how long before your ear gets a 'sunburn,'" he explained. "And that applies to every headphone there is."
A big factor in all this isn't simply the music. It's our prolonged exposure to background noise, said Gail Gudmundsen, doctor of audiology for Etymotic, a Chicago-based developer of earplugs and headsets. "Background noise on an airplane can reach 85 decibels, for example. More than eight hours of exposure to that can lead to hearing loss. Each time you go up three decibels, safe exposure [thresholds] is half the time." That means if noise is up to 88 decibels, the limit is four hours; or 91 decibels it drops to two hours; and so forth.
The clincher for iPod and iPhone users is that a good number are ratcheting up the volume to fight that kind of background noise -- whether it's a plane, train, automobile ... or whatever. "Unless you're a loudness geek, the reason you're turning it up too loud is to overcome what's going on around you," Dr. Gudmundsen said.
Isolate or Cancellate
That is why experts say a sound investment in the right kind of headphones can play a big part in prolonging your listening pleasure. There are a number of noise isolation and/or noise cancellation type offerings that are specifically designed to ensure that people keep volumes at safe levels.
Noise isolation is a "passive" approach that refers to any design that seals the ear canal to dramatically reduce outside noise. "Since the main reason people turn up volumes to unsafe levels is to overcome background noise, you won't have to if you seal your ear canals," Gudmundsen told MacNewsWorld. Etymotic produces a number of in-the-ear noise isolation products, including a family specifically designed for iPods and iPhones.
Noise cancellation headphones, such as the QuietComfort 2 developed by Bose, use phase inversion to neutralize low pitched sounds, such as the hum of a motor or the drone of an airplane cabin. "They work best in any situation where a background noise is constant and intrusive," says Fligor. "If they push up against the head they can also provide isolation for high-pitched sounds."
In his books, a good in-the-ear noise isolation is the preferred option. "Noise cancellation technology also works well, but may be more appropriate for situations where you can't find anything to fit your ear canals or you are prone to ear problems." Noise cancellation headphones are also bulkier, so not ideal for active users who like to listen to music on the run.
For those who can't handle the in-the-ear variety of headset and like full ear coverage, Ultrasone offers an alternative with its S Logic "natural surround sound" technology. The surround sound reduces direct pressure on eardrums and allows listeners to lower volume levels without sacrificing sound quality, Paul Taylor, president of Ultrasone, told MacNewsWorld. "Basically you end up with good isolation through the ear pads [fitting over the ears]."
Custom Thinking
Noise isolation headsets can be especially effective if you invest a few more dollars in custom-fitted sleeves, according to Ross Harwell, and audiologist with Hear Toronto, an audiology clinic in Toronto, Canada. Custom-fit headsets or earplugs are no longer exclusively for musicians with deep pockets, Harwell told MacNewsWorld. "It's interesting to see companies like Sonomax that specialized in hearing protection for industrial workers is now offering custom-fit products. It just shows how the idea is trickling down to the masses."
At the same time, anyone looking into custom-fit products needs to do their homework, he told MacNewsWorld. "Using online services that send you kits to make your ear mold impressions is a horrific idea and could do serious damage to your ear. A lot of audiologists and/or hearing clinics can do it for you at a reasonable cost. Many of those will also sell the headsets and, in some cases, will make the sleeves on-site."
In choosing the right headsets, Harwell notes that factors you need to consider include the sound quality, the fit and the coupling mechanisms (e.g. Etymotic headsets have multi-flange tips that stick out of the ear, Westone have tips that fit flush with the ear).
Whatever the investment of choice, Harwell notes that ultimately, common sense is still a principal factor. "You can have all the sound isolation you want, but you are still able to blast yourself at dangerous levels."
Look at it this way, Gudmundsen says: "Noise is noise is noise. It doesn't matter if it's a violin or an electric guitar. If you can hear music from a person's headset three feet away, then it's probably too loud."
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