[ponkine]

Several points would make my dreamed headphones, divided on 2 main subjects: Sound quality and comfort/use
 
I - Sound quality (not particular order)
 
1- Great bass extention. Not boomy but with authority. Able to separate between bass drums and bass notes from keyboards, basses and other instruments
2- Clear mids with warm feel. No voices sibilances, no harshness. Great sense of air, space and integration. Great soundstage
3- clear highs WITHOUT being bright/shrill. This is one of the hard-to-find point on headphones
 
II - Comfort/use
 
1- Excellent comfort on ears and head to use them for long periods (over hours) without any problems
2- Good impedance and qualities to drive them WITHOUT an amp. 
3- Good portability enough. Carrying bag must be included
4- Chord should have 2 lenghts: one for portable devices (something like 1,2 mts) and extention for hi fi devices (another 2- 2,5 mts). Cable should not come from both sides. 
5- Isolation: if closed-back, good isolation not to hear what's happening around, yet keeping soundstage and musicality
6- Look: great design.
 
 
and many others 
 

 

[Trance88]

For me, I'm all about accuracy. I want headphones that reproduce the sound the way it was meant to sound in the recording studio. I look for a flat sound signature or at least somewhat flat with a little extra bass extension. I've also got a soft spot for vintage headphones. The Pioneer SE-30 in my opinion has the best overall sound signature I've ever heard in a pair of vintage headphones. Slight midrange bump and slightly murky in the highs, but overall not bad. For newer headphones I'm pretty content with the Fostex T20. I'm still looking for a decent on the ear or over the ear pair for portable use. I'm ok with my Sony MDR-V150's, but I really want something a little better. 

 

[Jojomite]

i like detail and good airy treble

 

[dyl1dyl]

If you can bear the weight, the Audeze LCD 2 is fabulous.

 

[Mach-X]

For me, it's the lowly HD280 pro. Built like a tank, comfortable as all hell, unbreakable cable, relatively flat response. It lets me hear the recording, not the headphone. Sensitive but not harsh. "Oh but you haven't heard the or the". You're right, I haven't. And I don't care to. I'm 35 years old and not interested in chasing a unicorn I will never find. If I have to mod a headphone to get it to sound right, it isn't a good headphone. If I need a specific amp for my headphone, it isn't a good headphone. The HD280 pro delivers whether plugged into my nokia Lumia 520, the headphone out of my 1978 Sony separate amp/tuner or driven from the speaker out of my kenwood receiver bought in 1994. Whether listening to Whitechapel from cd, or Mike Oldfield on a 40 year old lp, they deliver powerful distortion free sound, and blank out enough of the outside world to allow me to get lost in the recording. That to me, is a great headphone.

 

[Boochie]

  "Oh but you haven't heard the or the". You're right, I haven't. And I don't care to. I'm 35 years old and not interested in chasing a unicorn I will never find. If I have to mod a headphone to get it to sound right, it isn't a good headphone. If I need a specific amp for my headphone, it isn't a good headphone. The HD280 pro delivers whether plugged into my nokia Lumia 520, the headphone out of my 1978 Sony separate amp/tuner or driven from the speaker out of my kenwood receiver bought in 1994. Whether listening to Whitechapel from cd, or Mike Oldfield on a 40 year old lp, they deliver powerful distortion free sound, and blank out enough of the outside world to allow me to get lost in the recording. That to me, is a great headphone.

 
 
Well said.  ^^This guy gets it....^^^
 
I feel the same way.  Right now, I have on my HD 595s listening to Howard Shore's score of The Hobbit--The Desolation of Smaug Soundtrack and the HD 595s are making me feel like I am in a movie theater. 

 

[corporatetool]

For me, it's all about replaceable parts. Sweaty drunks in clubs are always trying to break my equipment.

 

[UNIFi]

A perfect headphone for me would be a headphone that is durable - possibly metal, fully modular and can have any piece replaced, large soundstage with strong imaging and separation, warm sound signature with powerful sub-bass and bass authority for both rock and edm, slightly rolled treble but not muffled or lacking detail, light and comfortable. Would be like a more durable, stronger sub bass and more detailed version of the HD600 with the T1, HD800 sized stage.
 
Looks and isolation matter less for me.