I'm sure to get in trouble for asking this question, but do expensive cables make the sound any better than what comes with the headphone? My reasoning involves the "bottleneck" concept, where somewhere in the chain of components and accessories is the item with the worst quality.
Maybe the bottleneck is the metal in the PCM board, the soldering spots, the wires in the computer or amplifier/DAC, the cheap components used in the headphone port, and possibly MOST important, the very thin wires that lead from the headphone cable to the actual drivers themselves. These driver cables, even on the most expensive headphones, are usually a hair thing. A hair!! Surely these little and probably cheaply manufactured barely macroscopic cables should be considered as the bottleneck. Whatever the bottleneck in a system is, it just doesn't make sense that the manufacture supplied headphone cable would be the bottleneck.
If the bottleneck comes before the cables, then the original cables (or upgraded cables) really wouldn't even make a difference. If the bottleneck comes after the cables, such as the tiny driver cables, then the regular headphone cables aren't the bottleneck either. Either way, I just don't see how upgrading to a $200-$400 cable would make a difference, especially when all the information has to go through those tiny driver cables.
Okay, go ahead, haze me.