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Order a pair of Etymotic Er6i's from Amazon (usually the best price at around $75) - the best headphones I've ever had. I bought them to wear under my motorcycle helmet (because they're tiny) and now use them absolutely everywhere. My favourite is on planes - far superior to anything noise canceling as they block all ambient noise and sound great.

Those are awesome in-ear monitors and I have a pair that I use with all my portables. However...you're using these on a motorcycle?!!! What the eff are you thinking?! These things seal out almost all noise. I don't even jog with them because of that. Wearing them on any moving vehicle or even around moving vehicles presents a danger to you and everyone around you. Do the world a favor and get some that let you hear that car honking or tha t18 wheeler coming up behind you.
 
For anyone wondering if better IEMs (in-ear monitors) are going to make a difference over stock the answer is this: It depends. It depends on how sensitive of an ear you have and how good the replacements are. You can spend 80 to 100 bucks though and get a significant sound quality increase over stock. Two good choices in that price range are the Etymotic ER6i and the Head-Direct RE2 (available online directly from head-direct). If you want Uber-bass you won't get it with those IEMs because they are focused on delivering an accurate representation of what your music player is playing, not a sound image that is exaggerated in the bass end. If you do want some that exaggerate the bass then (from what I hear) you should look into the V-modas or bass freqs or something along those lines. I'm only interested in accurate sound so I haven't explored those.

The Etymotics are awesome...you can really hear things that you wouldn't hear with the stock buds. I love 'em but they do seal out most external sounds.
 
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