Background and Expectation:
I am fan of over-ear dynamic headphones. I have or had many dynamic headphones, but I have never own a planar dynamic before. I plan to buy the Audeze EL-8 as my first taste of planar dynamics. I choose EL-8 for 2 reason:  1. It is one of the newest planar dynamics headphone and featured with Fazor Tech.     2. Price. I only plan to spend less than $1400 (a common price for a dynamic flagship).       3. Comfort. I heard that Hifiman HE-560 has too much clamp force.
I expect to be impressed by EL-8. (And it does)
 
Review is based on   1. Sound Quality- a.Sound stage,    b.Treble, Mid, Bass     c.Detail&Sound Signature               2.Comfort            3.Portability               4. Appearance         
Headphones involved in the comparison:  AKG K812 & Denon AHD-7100 (Both claim to be easy to drive just like EL-8),      Sony MDR-z7 (Same price)
DAC&Amp: Denon DA300+SPL Phonitor Mini, Fiio E17K
 
1. Sound Quality 8/10   -----As Sum-up, it is a great sounding headphone. It has decent sound stage, balanced sound, and warm sound signature.  (I do not have any professional equipment to qualify the sound output of each headphones, sound quality review is purely based on my personal opinion)
 
a. Sound Stage.  -----K812 >>> EL-8 >= Z7 > AHD7100       For reference: Senn HD800 and T1 both has similar sound stage as K812.  Z7 is semi-open can (closed can with bass port)   AHD7100 is closed
      Sound stage is definitely not EL-8's advantage. K812's sound stage presents a live performance in a concert hall.  AHD7100 is like let the musician perform exclusively for you in a small room. EL-8 and Z7's sound stage is hard to describe.   I have heard Audeze LCD-X and LCD-3 at audio store, the sound stage of these headphones is much narrower than K812 also. If considering LCD-X costs 1.7K and LCD-3 costs 2K, audezes' sound stages are really not good.
 
b. Treble--EL-8>K812>AHD7100>Z7     Mid--K812>EL-8>AHD7100>Z7            Bass--K812>>EL8>Z7>AHD7100
    I have nothing to complain about the highs of EL-8. It is precise and controlled. But I am surprised about the mids of EL-8, especially when playing vocal. It sounds just like someone sing the song by your ears.  The bass is also controlled, but rather too weak.
 
c. Detail--  K812>Z7>EL8=AHD7100. If you are not a sound engineer or studio professional, I think the detail level of EL-8 is good for most type of music listening. 
    Signature --Warm and neutural. 
 
 
 
2. Comfort 9/10  -------As Sum-up.  EL-8 is a extremely comfortable headphone. I have wear it for 2 hour straight indoor, no discomfort occurs.
                           Weight: EL-8 460g> K812 390g> AHD7100 370g > MDR z7 335g-------Just for reference, it does not mean anything. EL-8 is the heaviest one, however you will not feel neck and shoulder muscle fatigue after long time usage. 
 
3. Portability 8/10 ---------As Sum-up, you can drive this headphone with anything cellphones or mp3 players. I have tried iphone 6, LG Optimus G-pro, Ipad Air, HP stream 7, and Ipod Shuffle. 
                               Portability: AHD7100>MDR z7>EL-8>K812.-------------Still, this does not mean anything. Most of these headphones are open or semi-open can, you will hear a lot of outside noise if you use them on-the-go; and the people next to you will hear what you are listening to very clearly.  I put AHD7100 at first purely because it is a closed can.
                        Easy to Drive:  AHD7100>K812>MDR z7>EL 8.--------------I have use Fiio E17k as DAC/Amp to drive all of them, and EL 8's output sound intensity is the lowest one of them all. On paper, EL-8 has the same efficiency as MDR z7, however, maybe MDR z7 is semi-open it sound louder than EL-8 which is open.
 
4. Appearance 7/10 --------- As Sum-up. I like the design and look of EL-8. However, the wood ring design always remind me of HE-560.
 

 
I have to talk about my expectation on this Headphone first. 
I am not a senior audiophile. 3 years ago, my first pair of AKG K601 lead me into this wonderful world of audiophile. This pair of AKG K601 showed me what is true sound of high fidelity, sequentially I bought some other AKGs, Beyers, and Sennheisers; I felled in love with all of them, and developed a bias love of European headphones.
For a long time, my bias love of European headphones made me reject all the Japanese headphones; until 1 years ago, my friend gave a me pair of Denon AH-D 600 as gift, and this headphone surprised me.  The sound of Denon AH-D 600 is not as neutral as AKGs, and not as spacial as Sennheisers; but the sound of it is so fun, so vivid, and its emphasizing in bass sounds great.Taking its price in consideration, AH-D 600 comes the best "quality and fun per dollar" headphone, it makes me start to think that Japanese headphones have high performance vs price ratio. Not long ago, I bought Denon AH-D 7100, and I think it is great, too. The sound stage of AH-D 7100 are not as wide as the open cans, but it presents a exquisite sound stage to you; it just like the country Japan, small but every bit of it is meticulous handcrafted. 
Sony is one of the major audio manufacture of Japan, I think I should give their headphone products a try (especially, their R10 has so many fans). Therefore, I bought this pair of Z7 as my first taste of Sony headphone, I image it will sound fun and addictive, just like Denons.
However, I am disappointed!! The build quality and wearing comfort of this headphone are great and beyond doubts. The sound is thin, dull, and extreme ordinary, (maybe I have too much expectation on it) it's not the sound I expect from a pair of flagship headphone of one of the major audio manufacturers in the world; it's sound like an average pair of $200 headphone, other than that, I cannot find any other words to describe it.
 
(The set-up I used-1. PC>Denon DA300>SPL Phonitor Mini> Sony MDR-Z7, PC>TEAC UD-H01>Lehmann Linear> Sony MDR-Z7)
 
(I apologize for my writing skill, if you find this review is hard to read, sorry)