iPhone + AMP vs. FiiO X3

[Merackon]

Sound quality wise, is there as much of a difference between using a FiiO X3 and an iPhone 6 using something like an E12A?

 

I ask because I just received my X3 and have been messing around with it. I like the hardware bass and treble adjustments, allows me to easily get my U curve that I like in audio. I hear that the iPhone 6's CL DAC chip is very good, so if I were to connect an amp to that, would it produce sound quality approximately equal to that of the X3, using a mix of iTunes AAC and piano music encoded in ALAC?

 

I am driving 250 Ohm headphones (770s), which is the reason why I brought the X3; media player, high quality DAC and an amp capable of comfortably driving them.

 

Thanks in advance,

 

Jack