[inarc]

So i ordered a pair of sennheiser HD555s and after reading some forum posts I realized that I might need an amp. but do I really? How much better is the sound quality with an amp? What im asking is, is the increase in sound quality so incredible that it justifies paying more than the cost of the headphones for an amp?

 

[Mad Max]

If in doubt, grab a Lisa III. 

 
Okay, okay, you might get some improvement with an amp.  You can try a cmoy or soemthing.  Some HD555/595 owners would better know - the search function at the top of the page also goes through people's profiles so you can get the opinion of individual users or you can ask in the respective appreciation thread(s) for those headphones.

 

[LantherZero]

Yes, the HD555 benefits greatly from an amp.Most headphones do, really. I'd not pay more than the cost of the headphones, though. Build or get someone to build for you a cmoy.