i like the sound of my K44s BETTER than the sound of the $200 sennheiser HD25s i bougt for a reduced price of $94 and ended up returning in favor of the K44s as the 44s have more bass and less brightness. i gave up on the HD25s after beating the crap out of them with 20 hours worth of "hear it across the room" dubstep after which they still never opened up where the 44s had more warmth right out of the box.
the 44s are still a little light in the bass department if you're producing bass heavy tracks, but unless you have infrabass, you can at least hear the bass clearly. other than some bass politeness easily remedied with some bass boost and an amp with juice (i'm mostly using them on mp3 players) they have a pretty flat sounding EQ with plenty of detail, particularly in the treble where you hear EVERY grain of sound in white noise & siblants making hihats you never heard before jump out and some stuff with too much treble piercing. the attack on these is INSANE! they don't just sparkle, you get that piercing sound you "feel in your neck" off of clearly recorded metallic percussion. i'd say the sound leans towards ruthlessly revealing and analytical. if you overdo the treble or muck it up, K44s will let you know which is a good thing. i've discovered 1 or 2 tracks that have hi-hats a little hot in the mix that were previously obscured with other cans and have heard many details in tracks i've listened to hundreds of times that i'd never heard before, especially low level crackle on vinyl. they are generally relaxed sounding though and even fun with good source material and don't complain when you drive them hard. i like mine except for the lack of deep bass on dance tracks, especially with puny mp3 players. they DO get a little uncomfortable on long sessions, but nowhere near as bad as head clamping sennheisers can get.
i can't remember the sampson SR-850s i had well enough to make distinctions, but at $40, those are a great value too and very similar sounding. a little light on the bass, but plenty detailed & relaxed sounding for critical listening with maybe a little but more warmth in the treble. that could be due to those being semi-open designs. i THINK the 850s might be more comfortable as i literally wore them for days on an inerstate bus trip and don't remember being uncomfortable. BOTH the K44s and SR-850s have low clamping pressure. i think i'd probably go with the SR-850s again given a choice, but those weren't available locally. i also got a really SWEET combo deal of just $50 for the sampsons including a nice, though a little hissy large diaphragm mic that's nice for home studio use, especially with louder sources.
there's an even CHEAPER AKG knockoff similar too the sampsons that might even be a rebrand of the same thing with slightly different earcups i think was just $30 (superlux HD668B). if the drivers are the same, that's an huge bargain though the 850s are tight too. the ONLY complaint i can remember about the 850s was not enough bass with everything else being clear, detailed and effortless even at volume. the 850s were great for helping me find low level tics in tracks to smooth out that were obscured by sennheiser 202s.
oh yeah... the isolation sucks on HD-850s too being semi open and all, but that's not an issue for studio recording and actually lets sounds breathe better. i bought them because they were the cheapest open phones i could find that weren't consumer junk and they were great for home recording and not so much so for riding the bus.
i'd say
go with the K44s if you want more bass, isolation and treble ruthlessness and the SR-850s if you want a more open & relaxed acoustic sound and the superluxes if they're otherwise identical.
the BEST idea though is to try and visit a music store that will let you open a box and audition their gear or that has gear on open display and bring an HQ source with stuff you're familiar with. there was a $60 pair of phones by an "off brand" at the shop i bought the K44s at that had really nice bass, but funky loud colors i didn't like and that weren't full over the ear designs or unknown name i didn't trust as much. nothing beats putting cans on and hearing them in person though break in differences can be an issue.
other than less bass than i'd like, both the AKGs and sampsons are otherwise excellent cans with plenty of detail and neutral EQs. hope that helps
