Already own Sennheiser HD215 and HD380 Pro. Looking at HD598 and HD600. Help!

[MF Kitten]

As stated in the title, i own the HD215 and HD380 Pros. These are in the same ballpark as far as sound goes, although they are different. The HD215 has less low end and a more "exploding" sound with lots of detailed mids, while the HD380 Pro has a deeper and louder low end with much more detail, and a much more extended high end that is also very smooth and even, and not all too hyped. After using the HD215 for a long time and then trying the HD380 Pros, i was skeptical, because the low end seemed so huge compared to what i was used to, and the high end seemed smoother than i was used to. After burn-in and getting used to their voicing, i came to love them. Much less peaky low end, and much more present and detailed mids, with a good high end airyness, again without any sort of sibilance or hype to speak of. I now realize the HD215 are a little "flat" sounding. Not flat as in "even", but flat as in "meh". Slightly anemic, though mostly in terms of frequency balance, and not in terms of the lows and highs missing from the sound. The deep lows and airy highs are in there, but they are kinda held back.
 
I have been using the HD380 Pro headphones for recording and mixing purposes, since they both isolate really well, and reveal any imbalances in the low end, any harshness in the high end, and any honk or scoop in the midrange. I am not looking to replace these, as they do a good job at being analytical, and the low end is impressive and tight, which kinda makes them a bit fun too. I am looking for something that will be more for the sake of listening to enjoy music, but not at the cost of being accurate and revealing (the HD650 doesn't seem like it'd be my kinda thing at all, because it's TOO smoothened and polite).
 
I am looking for something slightly more "prestigious" and refined, and i am specifically looking at open headphones. I want an open and balanced sound, as i can't stand it when i really notice hyped highs or lows in headphones, and i do not accept sibilant highs or bumpy lows. I want an even sound with great detail, nice open airy high end presence, and a deep low end presence. I know, that's asking a lot. Fatiguing headphones are a nightmare to me, hence i don't want presence boosts or high end peaks meant to hype up the sound a lot.
 
I've been looking at frequency graphs of different headphones, and just like i suspected based on my experience, Sennheisers are the most even headphones according to my standards. AKGs sound too hyped for my taste, and my experience is quite similar to the frequency graphs of their products, some more than others.
 
I have narrowed it down to the HD598 and HD600, although i have drooled at the HD800 too. Too expensive though, and it might have too much high end to it for my taste (or so biased reviews tell me).
 
I have one more important thing to add: I want them to be comfy! They shouldn't be too loose (which i hear is a common complaint about the HD598), and they shouldn't squeeze my head too much (like people say the HD650 does). I'd rather have a bit more clamping force than a bit less though. 
 
Finally, I am also open to suggestions with other brands or models.
 
SO, which of these two will fit my taste more? I'll be using them for mixing/mastering type stuff together with the HD 380 Pro and my studio monitors, but i'll mainly be using them as allround everyday headphones for music. I want to enjoy what i hear, but without too much coloration. And again, if others fit this descripition, be it a different Sennheiser or a different brand, let me know! Price range shouldn't be higher than the HD650, and i am talking "new" price, not "used" price.

 

[XxDobermanxX]

Both the HD 600 & HD 598 fits the bill
you could look into the hifi man he-400 though its nots as comfotable as the ones above 

 

[MalVeauX]

Heya,
 
I think simply a well balanced neutral phone would do what you're looking for:
 
Sennheiser HD600
Beyer DT880
Hifiman HE-300 r2
Hifiman HE-400
Sony MA900
 
Very best,

 

[vladinecko]

I own HD 598 and have auditioned HD 650 for a couple months. Though I can't comment on the 600, I can tell you 598 are the best full size headphones you can buy in their price range. Their sound stage is addictive and for the price, they resolve an incredible amount of detail. The sound is really engaging and fun.
 
The bass isn't anywhere near higher-end phones in terms of melodic abilities (I also own HD 700, HE-500 and have listened to HD800 on multiple occasions) but it's really good.
 
HD 650 takes you to a higher level yet so if you're deciding between 598 & 600. I'd strongly recommend going up another $100+ and shelling out for 650 (compared to HD 598). The sound stage isn't as wide as the 598 but you'll immediately hear clarity and more reference sound not found in the 598. 
 
In terms of comfort, 598 wins in all categories. It definitely sat on my head much better than HD 650. 
 
All in all, you're comparing HD 598 @ $250 (which can be had for as low as $180) to $400 HD 600. If you're leaning to more high end sound, spend another $12 and get the HD 650 (Amazon's current price is $412 - bloody fantastic!), you will not regret it!  

 

[MF Kitten]

Thank you all for your input! I've done a lot of research, and the AKG K601 is on the table too now, and i think they are the exception when it comes to AKG. Most other AKG headphomes aren't for me.