[ygi68592]

I currently own westones um1 in ear earphones with the latest ipod classic 160gb and a majority of music i own is 320 kbps.
 
Will i even need a portable amp? if so any recommendations?

 

[chef8489]

The um1's are pretty easy to drive so I dont feel you will not notice much a difference.

 

[Eric_C]

What do you feel is missing in your music? 
If you answer "bass", I would suggest changing earphones. The UM1s are not bassy, and will never be.