Originally Posted by cschiu
i'm sorry, does this mean that audio quality is affected if outputting to FP headphone?
I find the headphone amp on the Xonar card very neutral I.E. uncolored & very detailed. More so than the unmodded lineout. The modded lineout is practically identical sounding but with far less D.C. offset than the headphone amp has on the Essense STX. The modded lineout is what I recomend to anyone hooking an amp up to the Essense ST or STX as the D.C. offset is sufficiently low to drive any amp including D.C. coupled ones without issue.
In modded form the lineout is capable of neutralizing most of the D.C. offset emminating from the input circuitry of many amps which cannot be cancelled with the unmodded lineout. By cancelling most of the input D.C. offset it can reduce the D.C. offset at the output of the following external amp. This is a very good thing indeed.
The headphone amp though is great for driving headphones directly as the D.C. offset though too high to drive D.C. coupled amp is sufficiently low for driving headphones direct & is better in my opinion than whats attainable from the unmodded lineout driving an external amp as there is some loss in the coupling caps of the unmodded lineout.
Others do not of coarse always agree with me on this but that is ok with me as some types of music is easier on the ears when there is a certain degree of loss as long as it is not excessive & the coupling caps used on the lineout are not terrible but they do have some loss. I have heard a lot worse losses in coupling caps before than the ones used in the ST or STX.