[Awpward]

I have a pair of Sennheiser HD202 and am currently shopping around for a mid-range, somewhat portable fullsized headphone. I have been particularly keen on the Philips Fidelio L1, Sennheiser Momentum, and the Sony MDR-1R. While Ive heard great things about the first two, they didn't sound that great to me, perhaps somewhat muddy sounding. Have I just become accustomed to the sound of my existing headphones, and in time would appreciate the sound of the other headphones? Or is it likely that the way I perceive them now will stay the same?  

 

[tomb]

I can attest to the Momentum - it must've been a bad source or a weak amp.  The Momentums are a fine pair of headphones.  Rest assured, Sennheiser did not make HD202's into a better headphone than the Momentum.
 
As far as being accustomed to a certain pair of headphones, I've always found that goes out the window when something better is heard. 

  It's true that once you reach a quality plateau, the differences are slight, so it's not so easy to determine whether something you've heard is better or not, but you're a long way from that with 202's.
 
Just keep in mind that a pair of headphones may be fairly matched to the quality of the system it's connected to - bad enough, and a better pair of headphones may actually sound worse.  "Welcome to Head-Fi and watch out for your wallet" as they say around here.

 

[Awpward]

Cheers, that explains a lot.