Marantz SA-17S1's filter?

[Fafner]

I just got this player. I'll use it mainly with my HD650 paired with my Emmeline XP-7.


What do you sugget as filter setting (normal/custom)?
I couldn't find any hints about the frequencies that the filter cuts when set to NORMAL...when set to this position, is the full potential of the HD650 used?


Btw...the headphone-out is rated to a quite satisfactory 0.5W at 32 Ohms...is an amp needed for the HD650?

 

[Fafner]

Just found out that the filter cuts frequencies above 40kHz...thus, this should be higher than HD650's max frequency, right?

 

[Fafner]

I've tried to disable the filter putting the switch to "Custom". It doesn't seem to cause problems with both my HD650 (when attached to the player's own headphone output) or my XP7. The sound seems to become a bit more open...highs become a bit more prominent and soundstage seems to improve...


I must confess that I couldn't decide yet if I prefer to have my HD650 attached to the player's headphone out or to my XP7. The XP7 seems to give me a more consistent soundstage and some more bass, but the player's headphone amp (although the player's burn in isn't finished yet...I'm around 30 hours until now) seems to me a bit more fast, detailed and transparent.
Anyone with this equipment has some comments?