Considering several open headphones for Kawai ES920

[GabrielPhoto]

Hi!
Hopefully there are more digital piano players here that can share the feedback on favorite headphones.
I am considering the following models:
DT 990 Pro
DT 1990 Pro
Hifiman Sundara and the xs model
I have not considered any Senns yet because they all seem very weak in the bass department which I find not so nice when trying to reproduce a 9' grand bass LOL but if you like one, let me know.
Only playing Classical pieces. If I need a small amp that is fine. Currently testing the 990 Pro (250ohm) and without an amp using the HIGH volume setting its decently loud but not sure if I am missing something else by lacking the amp.
Thanks

 

[staticV3]

I have not considered any Senns yet because they all seem very weak in the bass department which I find not so nice when trying to reproduce a 9' grand bass LOL but if you like one, let me know.

The Sennheiser HD560S has about as much bass as the DT990 Pro, plus a more correct tuning all around:

560S: https://www.dropbox.com/s/7amvtfabcizrc12/Sennheiser HD560S.pdf?dl=0
DT990: https://www.dropbox.com/s/sqb4mgfgq86idwc/Beyerdynamic DT990 (fresh earpads).pdf?dl=0

 

[GabrielPhoto]

The Sennheiser HD560S has about as much bass as the DT990 Pro, plus a more correct tuning all around:

560S: https://www.dropbox.com/s/7amvtfabcizrc12/Sennheiser HD560S.pdf?dl=0
DT990: https://www.dropbox.com/s/sqb4mgfgq86idwc/Beyerdynamic DT990 (fresh earpads).pdf?dl=0

I got a 560s arriving in a few hours to test vs the 990.
Thanks