To give you an idea of where I'm coming from I have owned JH audio JH5 IEMs, Fostex T50rps, and Audio Technica ATH-M50x's. My Fostex T50rps were issued to me at audio engineering school and were what I used as reference for a long time and I loved their natural mids. My JH5's are also very flat as far as IEMs are concerened. i was not a fan of the ATH-M50x's (owned them for about an hour before returning and getting these Shures).
 
 
I'll keep this short and sweet. The sound is very neutral but at the same time not too flat. If anyone has ever been in a studio these don't sound like Yamaha NS10's. I'll give the Fostex that comparison tho. These sound flat/neutral but with a little bit of a relaxed midrange. They're still great for reference but you can really enjoy listening to music through these as well. I originally bought these because they were the winner of Dave Rat's headphone quest (He is the FOH engineer for the Red Hot Chili Peppers and if he recommends something live sound guys listen). And now I see why he recommended them. He actually compares the sound of a PA in an arena with some test music to the sound of the same test music going through these headphones because they sound that good. I'm so excited to be listening to these right now!!!!
 
I'm using this without a headphone amp into a macbook. and/or iPod. I will also take these with me to my cruise ship when I return from vacation (I am an audio engineer for Carnival Cruise Lines).