HE400S or not?

[LogicSound]

HE400S is a neutral headphone or bassy?
better than HD558 a lot?

for music... I dont have amp but I can buy if need that.
up to 250$ for headphone

these or monolith m560/m565?
or maybe HD6XX ?

 

[cossix]

I'd stick with the 400S if you don't buy an amp. The 400S with no amp should sound better than the 6xx with no amp from what I've read

 

[ProtegeManiac]

HE400S is a neutral headphone or bassy?

Closer to neutral.

better than HD558 a lot?

Objectively, yes.

Subjectively, whether yes or worth it for the money, we can't answer that for you.

or maybe HD6XX ?

These have a fair bit more bass than the HE400S.