Try a Diamond Reference Mini-Mini from Myo (rnb180).
I use 18" of this to hook up my portables with my mini amps. I also own Grado SR 225's (and formerly 125's), and can attest this cable really opens things up soundwise. And you wouldn't believe the bass!

Highs are always nice and clear too. I'm not sure on his present pricing, but I'm sure you could get the Diamond Reference Mini for around between $79 and $99.
You can contact him here on HeadFi, through the Members of the Trade forum. You can also view photos of his work through the links provided there.
He also sells on ebay, under the name RnBaudio.