[12many]

I guess that would narrow it down to the HD599.     There is a big cost jump (more than double) $143 to $328 for the jump between the two.    I am looking for a mellow pair of HP for the office.  Lent my HD598 to my Dad.  I have the HE-400i at home but I think it is too detailed and expensive for work.  I could use open or closed.  Comfort is a top priority and then nothing to bright or bassy so I can focus on work. 

 

[milosingh]

If they had something in between it would likely hamper the sales of both of these.

As far as I know, they don't have anything in between. Unless you're looking for more than just home Hifi. They have products in other sub niches that I'm not familiar with though.

 

[WilliamLeonhart]

How about you try some other brands? Like Audio Technica or AKG?

If you decide to stick to Sennheiser, I strongly suggest you look into some older models like hd540 or hd580. They're not necessarily worse than the hd600. Personally, I prefer the hd540 much more than the hd600 and hd650.

 

[12many]

 I did some searching and perhaps the ATH-M50x would work.   On the frequency charts the treble seems rolled off a bit (which would be good for my application) but the bass seemed a bit boosted.  I will look at some reviews.   Not sure about a closed headphone.  I don't mind some leakage.  I wonder if I can find them local to give them a listen. 
 
I will look at what AKG has to offer. 

 

[WilliamLeonhart]

Be sure to try the AD series as well. If you like the hd598 perhaps you'd also like the ad900x.

 

[serman005]

Be sure to try the AD series as well. If you like the hd598 perhaps you'd also like the ad900x.

If you are looking at closed, you might want to check out the SoundMAGIC HP150. It's fairly neutral and not ostentatious.

 

[PurpleAngel]

   I did some searching and perhaps the ATH-M50x would work.   On the frequency charts the treble seems rolled off a bit (which would be good for my application) but the bass seemed a bit boosted.  I will look at some reviews.   Not sure about a closed headphone.  I don't mind some leakage.  I wonder if I can find them local to give them a listen. 
 
I will look at what AKG has to offer. 

 
Check out the AKG K553 Pro, sometimes sold by Massdrop, so you would have to buy one used,
http://www.ebay.com/itm/AKG-K553-Pro-Headband-Headphones-Black-/111899500447?hash=item1a0dbadf9f:g:RT4AAOSw~OVWuGAP
http://www.head-fi.org/f/6550/headphones-for-sale-trade/-filter-/RmlsdGVyJTVCdHlwZSU1RCU1QjElNUQvMS9GaWx0ZXIlNUJzdGF0ZSU1RCU1Qk9wZW4lNUQvMS9GaWx0ZXIlNUJvcmRlcl9ieSU1RC9DbGFzc2lmaWVkLmNyZWF0ZWRfYXQvcGFnZS8w/
 
The ATH-M50X are bassy headphones, but I'm going to guess the K553 Pro offers better over all sound quality and better surround sound/sound stage.