Since my last post on this thread disappeared due to the forum going down earlier, let me repost this.
First off, try the pinhole mod and see if that works out for you. If not, go on to the next step.
Here's the step: Sony EX700LPs which can be had for $200. One of the most underrated in-ears on the market that gets occasionally mentioned on Head-Fi. These are dynamic phones that should fill you bill for articulate bass, bass impact, details, AND excellent soundstage (I would say that the soundstage for the EX700's outclasses all the armatures I've tried including the SE530s from Shure and also the nearest dynamic competitor, the Atrio m5s). They LOOK big but they sit snugly and flush with your ear so do not hesitate just by the odd shape and size of the EX700s. I would stay away from the Image x10s as they have a congested sound due to the fact that Klipsch has went with a bigger, warmer, bassier sound signature which results in a negative hit to the higher frequencies (thus causing the congested sound). This actually goes for the entire range of Klipsch in-ears except for the Custom-1s and Image x5's which I have yet to listen to. The EX700s makes the least compromises and retains a sound that is remarkably close to a good set of full size phones. Just to prove a point on how well the soundstage is presented on the EX700s, I've plugged every one of in-ears into a Dolby Headphone processor and demoed them with movies and first person shooters and the EX700s are the only ones that I can actually pinpoint different directions of sound with in a consistent manner. Needless to say, I don't usually use them for that purpose and they are usually plugged into my portable gear let that be my macbook, iPhone, and sansa clip when I'm out jogging. It comes up in spades.
Runner up is the Atrio m5s which is also in the $200 price bracket. The music presentation is a bit darker than that of the EX700s but still exceptional. Soundstage is also presented quite well but falls behind the EX700s. If you really really really need that deep deep deep sub bass, the Atrio m5s will serve you very well.
Now mind you, both of these are dynamic in-ears and I would highly suggest that you burn them in for a minimum of 20 hours before you start to listen to them seriously. My Sony's are at around the 200 hour mark now, I would say that around the 100 hour mark, they were pretty much silky smooth.
Last and final note, the Sony's are incredibly efficient phones and they run great with anything you plug them into, limited only by the quality of your source player. Plugged into my Tomahawk, the Sony's gain a bit more control throughout the spectrum as well as a nice increase to it's already remarkably large soundstage.