Originally Posted by uchihaitachi
The X3 has been designed to sound audibly transparent. iMod has treble roll off and people have tended to call it 'warm sounding', also it largely depends on what amp you use with the iMod.
No, iMod doesn't have a treble rolloff. It might have bass rolloff if the output caps are too small. However, the selection of output caps will greatly affects the tone of the output - the favorite for many iMod is the BlackGate HiQ and it is actually a dark sounding cap, hence why many believe the treble is rolloff (which isn't, as measurement has been done). If you do an iMod with other caps you won't find it to be that dark sounding, and quite possibly the opposite. Personally I much prefer Nichicon Muse or Oxicap over BlackGate.
Originally Posted by zenki14
What I read on ClieOS's impressions is that the X3 headphone out may be a bit towards bass so he did an op amp solder swap to hear more treble out of it.
Even though X3 measures perfectly flat, it might not 'perceived' flat. Opamp has each has its own 'tone', so to speak. You can make them sounds as transparent as you want if optimize the whole amp section for it, but it won't be practical to use it that way in a portable player. O2 will be a good example for that.
Originally Posted by bowei006
I wonder if the Burr Brown OPA627 will work with the X3 because if it does work. Well let's just say that after my review is done. I'll master the art of SMD soldering
OPA627 is mono channel and very high in output impedance, so it is not suitable for portable purpose unless you have the space for 2 chips and implement a buffer stage after them.
Edited by ClieOS - 6/28/13 at 7:30pm