hakushondaimao
Headphoneus Supremus
To be fair, an amp *shouldn't* alter the sound in any way. So, my best guess is that the sound improvement is not because of the amp, but because the line-out is being used
Surely a DAP with sub-par internal amplification will sound better when played out of LO to a quality external amp.
And likewise, a DAP with quality internal amplification played out of LO to an external amp that has a totally different sound signature will sound different.
If the 2nd generation X3 has a similar sound signature to the E12A, then there should be little differentiation when A/B tested (DAP vs DAP+Amp) against each other. This is what I've experienced when the E12A is paired with the X3 2nd Gen. with bass boost off. With bass boost on, the combo sounds different than X3 alone (assuming one doesn't play around with EQ). With my Picollo, which has a slightly warm sound sig., I hear a subtle difference.