[Avean]

Difficult question but this kinda screwed with my head a bit. I've used the Sennheiser HD700 for about 5-6 years now. When i first got em they sounded horrible so i had to use EQ to make em sound good. (EQ profiles from this forum).
Recently the wirings on em stopped working so i figured i would use my Sony XM4 through bluetooth while i figure out a new pair to buy.

What surprised the hell out of me is that playing games with the Sony XM4 it actually sounds way better. Sounds are more detailed, the binaural audio in games like Hunt: Showdown that i previously thought needed virtual surround on top of it sounds amazing now and i can pin point enemies way better.
Now this doesnt make sense at all considering HD700 is open-back headphones with good soundstage. I used the HD700 in pairing with Soundblaster G6 for the amp but all settings was plain stereo only.

So either the HD700 isnt that good for gaming like i previously thought or the blame is on the EQ settings but i remember i have played without it before and sound is very flat with those headphones. Here is my EQ config if anyone want to see if this messed up the sound too much.

Filter Settings file
Room EQ V5.00
Dated: October 15, 2014 5:51:23 AM
Notes: Sennheiser HD 700 Flat Balance + Super Bass = Big & Wide Soundstage with a nice fat BASE!
Equaliser: Generic
No measurement
Filter: ON PK Fc 10 Hz Gain 10 dB Q 8
Filter: ON PK Fc 20 Hz Gain 8 dB Q 8
Filter: ON PK Fc 30 Hz Gain 8 dB Q 8
Filter: ON PK Fc 40 Hz Gain 8 dB Q 8
Filter: ON PK Fc 50 Hz Gain 8 dB Q 8
Filter: ON PK Fc 60 Hz Gain 8 dB Q 8
Filter: ON PK Fc 70 Hz Gain 8 dB Q 8
Filter: ON PK Fc 80 Hz Gain 8 dB Q 8
Filter: ON PK Fc 90 Hz Gain 8 dB Q 8
Filter: ON PK Fc 100 Hz Gain 8 dB Q 8
Filter: ON PK Fc 200 Hz Gain -5.1 dB Q 8
Filter 12: ON PK Fc 300.0 Hz Gain -4.8 dB Q 8.00
Filter 13: ON PK Fc 400.0 Hz Gain -3.3 dB Q 8.00
Filter 14: ON PK Fc 500.0 Hz Gain -2.3 dB Q 8.00
Filter 15: ON PK Fc 600.0 Hz Gain -1.5 dB Q 8.00
Filter 16: ON PK Fc 700.0 Hz Gain -0.9 dB Q 8.00
Filter 17: ON PK Fc 800.0 Hz Gain -0.5 dB Q 8.00
Filter 18: ON PK Fc 900.0 Hz Gain -0.1 dB Q 8.00
Filter 19: ON PK Fc 1000.0 Hz Gain 0.1 dB Q 8.00
Filter 20: ON PK Fc 2000.0 Hz Gain 6.2 dB Q 8.00
Filter 21: ON PK Fc 3000.0 Hz Gain 6.7 dB Q 8.00
Filter 22: ON PK Fc 4000.0 Hz Gain 5.0 dB Q 8.00
Filter 23: ON PK Fc 5000.0 Hz Gain 3.0 dB Q 8.00
Filter 24: ON PK Fc 6000.0 Hz Gain 1.0 dB Q 8.00
Filter 25: ON PK Fc 7000.0 Hz Gain -1.3 dB Q 8.00
Filter 26: ON PK Fc 8000.0 Hz Gain 1.0 dB Q 8.00
Filter 27: ON PK Fc 9000.0 Hz Gain 3.5 dB Q 8.00
Filter 28: ON PK Fc 10000.0 Hz Gain 7.0 dB Q 8.00
Filter 29: ON PK Fc 13000.0 Hz Gain 10.3 dB Q 8.00
Filter 30: ON PK Fc 20000.0 Hz Gain -0.5 dB Q 8.00

Edit: Seems replacing the headphone wires did the trick. Been many years and they probably been damage longer than i thought. Really missed the open-back sound from the HD700's.

 

[SilverEars]

HD700 just has a wonky FR. XM4 isn't perfect, but it's easier to listen to. For gaming use something practical.

 

[BrokeAudiophileMan]

HD700 was the right driver with the wrong tuning and the wrong cups. iirc 660S and 660S2 put the HD700 driver into an HD6XX shell and improve the tuning to make something you can actually listen to, unlike the HD700.

If you go back and look at reviews from when the 700 came out everyone complained about the tuning.

 

[MakeshiftApe]

Aside from what others already mentioned: If you don't have perfectly silent surroundings I sometimes find using a closed back can actually improve the authenticity of binaural recordings specifically/helps immerse you. I generally prefer the openness of open-back but if I don't have perfect 100% silence and I want to listen to a binaural recording my closed backs will do it better. So that might be why you're getting a better experience, especially for binaural audio.