[MrSpaceFox]

I'm upgrading from base level pair of Audio Technicas,
 
http://www.amazon.com/AUDIO-TECHNICA-Stereo-Headphone-ATH-PRO5MS/dp/B00094NNA6/ref=cm_cr_pr_product_top
 
and am stuck between two great pair of cans; the Audio Technica ad900x  and the Beyerdynamic DT990 Pro250. Both have excellent reviews and can be bought for about 150-200 US dollars. I understand the drawbacks of open ear phones, but I am very interested in the detailed highs and open "soundstage".
 
http://www.amazon.com/Technica-ATH-AD900X-Open-Back-Audiophile-Headphones/dp/B009S331VU/ref=sr_1_cc_1?s=aps&ie=UTF8&qid=1402030904&sr=1-1-catcorr&keywords=ad+900x
 
http://www.amazon.com/Beyerdynamic-DT-990-Pro-250-Professional-Acoustically-Applications/dp/B0011UB9CQ/ref=sr_1_4?s=electronics&ie=UTF8&qid=1402029570&sr=1-4&keywords=ad700x
 
I will be using a cheap e06 fiio driver and mp3s for the time being. I will be listening to anything from light rock to electronic soundtracks.
 
What kind of sound upgrade am I looking at from my old, but reliable cans, and which do you guys think is the better choice. Please excuse any of my ignorance toward the subject, and all help is greatly appreciated!

 

[KG Jag]

These two have different sound signatures.  One is more neutral and the other more colored and (to some) "fun". 
 
What sound signature are you seeking beyond the two things you have mentioned?

 

[Me x3]

Hi,
 
Beyerdynamic DT990 250 Ohm really need a powerful amp to sound good, something like Fiio E10 could drive them just fine, but won't extract their full potential.
 
AudioTechnica AD900X should be much easier to drive.
 
In my experience DT990s shine -when properly driven- with well mastered music (mostly audiophile recordings), and tend to sound over-bright/sibilant with most modern (over compressed recordings), specially female vocal recordings.
 
AD900x should be smoother and more neutral sounding.
 
SoundMagic HP200 also comes to mind, these seem to fit your requirements very well, I'm not sure how much they cost nowadays.

 

[MrSpaceFox]

I want something that is distinguished but relaxing; it's hard to describe without proper terminology... I basically am looking for clear mid/treb and controlled bass. My musical palate will be ever changing so I can't pinpoint a certain genre. I am also very interested in the broad and diverse soundstage many claim open headphones provide.
 
I value comfort, but i'm sure just about anything will be better than my current, on ear ath pro 5s.
 
Which would you recommend? 

 

[Me x3]

  I want something that is distinguished but relaxing; it's hard to describe without proper terminology... I basically am looking for clear mid/treb and controlled bass. My musical palate will be ever changing so I can't pinpoint a certain genre. I am also very interested in the broad and diverse soundstage many claim open headphones provide.
 
I value comfort, but i'm sure just about anything will be better than my current, on ear ath pro 5s.
 
Which would you recommend? 

You should consider Sennheiser HD598.

 

[MrSpaceFox]

Those may be slightly superior and fit my criteria like a glove, but unfortunately i'd like to spend a but less than that. Also, I prefer a more minimalist design... Would the dt990s with an e10 be able to compete with the sennheisers? (Overall sound quality)

 

[MrSpaceFox]

I didn't realize how much that amp was actually... I may be better off sticking with a sub 50ohm pair

 

[KG Jag]

The 900X best meets your description of what you are seeking.  It does well without an amp.
 
This is an excellent piece describing the 900, which the 900X replaced:
 
http://www.head-fi.org/t/634201/battle-of-the-flagships-58-headphones-compared-update-audeze-lcd-2-revision-2-6-4-13#user_ATHAD900

 

[MrSpaceFox]

That is where i was leaning. I believe that many of the mentioned negative aspects were improved with the "x" version, and I am happy to see that the professionals (per say) believe they are an A+ when it comes to price vs. quality!

 

[MrSpaceFox]

Also, do you think that the 700x's would still provide adequate quality and a significant step up from my old cans?

 

[Me x3]

  Those may be slightly superior and fit my criteria like a glove, but unfortunately i'd like to spend a but less than that. Also, I prefer a more minimalist design... Would the dt990s with an e10 be able to compete with the sennheisers? (Overall sound quality)

Well, sound quality is a quite diffuse and controversial topic.

If sound quality is for you a synonym of smoothness and neutrality, then the answer is no.
 
If sound quality is for you a synonym of detail retrieval, fast decays, crystal clear treble, textured lower mids, and impactful bass (Bass in real life is impactful... doesn't it?)
Then DT990s are superior by a wide margin.
 
Warning!
DT990s are bright, analytical and high resolution headphones that will show most flaws on the recordings, especially at high frequencies, so they won't fit many genres, and that's why so many people hate them. In my experience, playing poorly mastered music through them is not a good experience definitely, neither playing very old recordings with some background noise/hiss. Some warm jazz recordings tend to sound too warm through DT990s, and some metal wind instruments can sound overly bright and often annoying at mid/high listening levels.
 
That said, with the right recordings, DT990s are simply amazing and quite unique headphones, and also their price is a joke!

 

[KG Jag]

  Also, do you think that the 700x's would still provide adequate quality and a significant step up from my old cans?

I have only heard the older 700.  The 900/900X is a full tier above the very bass light 700.

 

[Me x3]

If you don't want to spend too much money you should consider Pioneer Se A1000. Amazing headphones at their price point. Wide soundstage, pretty neutral and relaxing signature, maybe a bit veiled, comfortable, easy to drive, forgiving of not audiophile recordings. Also good build quality. Their cable is a bit too long...

 

[MrSpaceFox]

The 60 dollar price tag was discerning, but it seems that they are praised by many enthusiasts because of the price/performance ratio. How much better would the AD990xs be in comparison? (Factoring in build quality, comfort, and sound quality- which I understand is an amorphous subject)

 

[redrich2000]

Get the AD900X. They're excellent.