Headphones "tattle" if you crank the volume
 

*Source: TechnologyExpert (http://technologyexpert.blogspot.com...u-crank.html)*
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There has been a lot of attention paid to hearing loss and MP3 players (http://www.realtechnews.com/posts/2625), especially ones that use earbud headsets. Although some vendors such as Apple have included updates to their software (http://technologyexpert.blogspot.com...ts-in-new.html) which allows parents to lock the volume level, most do not.

Here comes a set of headphones that, although they don't lock the volume level, readily lets you know if your kids have raised the volume to an unsafe level (most likely this product will go over like a lead balloon with teens). The Guardian HA-31 headphones, by Hamilton Electronics (http://www.hamiltonelectronics.com/), has red and green LEDs on the earcup. If you can't guess, red means "too loud".

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