I plan on buying a pair of open cans to go along with my m50s. I'm sur emost of you know these are a bit bass heavy.
I will be running it through a fiio e11 amp.
My Budget is $300-$350
Philips X1/28 Fidelio, $290.
I'm guessing with those you would have no problem selling off your ATH-M50s
Or save a few dollars and get some used Audio Technica ATH-AD900X ($160?).
(I own the ATH-A900X closed version).