>>106576987
No. Adding a bass shelf big enough to make these Harman compliant will cause them to distort. Any low distortion planar is the endgame of headphones once properly EQ'd.
>>106576993
FiiO K11 is less than $150 and is decent. Just don't get the R2R version, that one uses a chip that's worse than 40 year old DACs, since R2R is an inferior chip type.