[mesmerized]

There have been studies that have shown that better isolation allows you to actually turn the volume *down*, and therefore being better for your long-term hearing. Headphones that do not isolate well force your to increase the volume in order to hear the music and drown out the noise. High SPL is what damages your ears. Anything you can do lower the net SPL is a positive.

I'm afraid I'm not sure what SPL stands for. Sound performance... level?

 

[billybob_jcv]

SPL = Sound Pressure Level. Perceived volume is actually the sound pressure felt by your eardrum. SPL is typically measured in dB: http://en.wikipedia.org/wiki/Sound_pressure

http://www.etymotic.com/pdf/guide_safe_listening_earphones.pdf
http://www.etymotic.com/publications/erl-0136-2006.pdf
http://www.westone.com/defendear/index.php?option=com_content&view=article&id=92&Itemid=111

 

[mesmerized]

Thanks for those links Billybob. I'm reading the first pdf now and there's one question that has popped in my mind... It seems that IEMs are a truly wonderful solution with their sound isolation... If so, what's the advantage of having on-ear headphones??? 

 

[epicFAIL]

  Thanks for those links Billybob. I'm reading the first pdf now and there's one question that has popped in my mind... It seems that IEMs are a truly wonderful solution with their sound isolation... If so, what's the advantage of having on-ear headphones??? 

IEMs lack soundstage; you will hear music deep inside your head while over ears offer bigger soundstage and more bass and other stuff.
that's all i know.