I was, until they recently got broken, using a pair of Sennheiser PX100s with my iPod Photo. They gave a really quality sound as expected.
As a replacement, and as they were reduced in a sale, I've bought a pair of PX200s. I thought that the closed design would be quite suitable. However, they aren't giving the same bass response that the PX100s used to.
Is this an electronics issues with the iPod, or is this a trait of the PX200 phones?
I've had both models and your right the 200's don't have as good bass
responce as the 100's but I ended up keeping them because of the better noise shielding from the outside world.
The PX200s bass response is definately not as good as the PX100s. You can try to improve it by playing around with the positioning on the ear, but to be honest, if isolation from external sounds isn't a problem, the PX100s are much better.