[Jefafa77]

Just a basic question, how far can a portable device take you (without a portable amp)? 
 
Open, closed, IEM's, etc...At what point does anyone notice a sizable difference between a portable player and something with a little more power? 

 

[Head Injury]

  Just a basic question, how far can a portable device take you (without a portable amp)? 
 
Open, closed, IEM's, etc...At what point does anyone notice a sizable difference between a portable player and something with a little more power? 

Depends entirely on the headphones and their power requirements. Just about any headphones but the ones designed exclusively for home use (your full-sized Beyers, high end Sennheisers, etc.) will be well served by a half-decent portable player, but there are exceptions. Take it on a headphone by headphone and DAP by DAP basis.