unless you're planning on using them for travelling a lot on noisy transport, then I would suggest active noise cancelling cans... however most closed cans usually do a good job of passive noise isolation, I would say that they would definitely do the job for noise isolation even when on transport, but ANC is worth getting, but only if you travel a lot, planes in particular, however cans or iems with a good seal and music playing at a decent listening level will still pretty much block out all background noises, even when on a plane...
But you have to make sure you get a good set if you do go down the anc route... e.g. the beats studio are anc, but they do an appauling job at it, my M50's do a much better job just with a good seal.
I have listened to a lot of headphones, please check my profile for some of what I have listed...
I would say that after 100+ listening to the M50's, I LOVE THEM, I have modified the hell outta them too... (but nothing to change/alter the sound sig intentionally).
The ultrasones look to be another good choice, I have read a lot of mixed reviews on the SRH-840's and generally people prefer the M50's, I read someone saying that the Shures had a more dry sound, and the M50's by comparison were warmer, Shures better for studio monitoring, but M50's better for music listening...
Well I can't make any comments for myself about the shures, but I can say I LOVE my M50's, especially after putting purple fluffy socks, and a detachable cable onto it...
From my voodoo'd SGS using PowerAMP, the M50 doesn't really need an amp, but if I want ridiculous amounts of bass the Fiio E5 does a good job.
Out of a motherboards built in soundcard (Realtek HD and the likes) the PA2V2 does a very nice job..
If you have a decent sound card, then amping won't benefit you by much, unless you're lowering the pre-amp and turning up the bass REALLY high, then just need the amp for a higher volume output... My 7 year old internal Creative Audigy 4 does a good enough job for my M50's unamped.
Other portable amps you might also consider, cMoy Bass Boost amp, Fiio E7 DAC/AMP and E11.
This is just devices on the cheap scale of the spectrum.. you could spend a lot more.
But the M50 really does benefit amping if your source doesn't have a good built in amp, e.g. all ipods/iphones will need amping to benefit the M50, and the above will do a very good job at it... not sure that it's worth spending a lot on an amp, if it's for the M50 anyway...
Music genres I listen to most of the time:
RnB, Hip-Hop, Rap, Rock, Classic Rock, UK Funky House, Electro-House, Chillout
