I'm looking for the best closed headphones under 150$, ones with the clearest most detailed sound, without exaggerated bass, which one of the two in the title will be the best? open for other suggestions as well.
I cannot recommend both of them Takstars are cheapish Chinese headphones like all the others in the same league they have something absent like cheapy sweating pads, some weird spikes or roll-offs these and they don't sound natural at all.
Ath-M40x are much more better than Takstars as build quality and sound but there is something missing and sounds synthetic somehow and not that accurate if you're looking for it. I cannot describe but i didn't feel good and sold them.
I can advice you Beyerdynamic DT 770 pros soo comfy detailed and far soo nice to use them if I need to compare this to two others. Or you can go through Shure SRH 840. You won't regret at all with these guys.