Did you try them amped ? they are incredible sounding I agree with that reviewer best buy below Hifiman HE500.
The momentum are a very narrow enclosed soundstage but very finely detailed and crisp punchy midrange bass and decent low end sparkly (personally I thought too sparkly treble), I went from momentum to x1 and couldn't be happier.
I have seen people likening the momentum sound sig to audio technica m50's which can be had for $100 or the cheaper amperior or sp 25 ii are better buys if style and looks aren't an issue.I like the momentums but really most of the money is in the lambs leather and build quality than drivers.
The X1, HD600, HD650, are a class above HD598 and Momentums.
Edited by c64 - 5/18/14 at 3:24pm