« Very good »

I had to try more than thirty headphones, including the HD 600, 650, Beyer 770, Sony MDR 7509, Grado SR80, Koss pro4AAT, STW, beats by dr dre, AKG k700i on 3 bose, etc. .. .
The Ultrasone Pro 750 has it caught my attention more than others, not he be better than everyone, but everyone has a little of its "domain". That the 750 is best for me.

I initially wanted to buy the 900 pro but given the prices of 750, almost 2 times less expensive, I decided to take the 750 initially.

Attention, I want to say that my impressions are made on a current material of shit (I repost a notice when I go back in France in qq months, with real stuff)

Dabord I tried the demo CD and I took a big blow: on some tracks, the ultra sound is natural, as if the sound came out very good speakers, I even like saying the live but it could say that I exaggerate.
Other tracks "show" the spatialization: applause and fireworks among others, which are reproduced in space, I would not surround sound but the spatialization is very good, the best I have heard for closed headphones, or even may be the best short, I would have to recompare listening.
The spatialization is different than the AKG 701i, which is very good too (but open), in short, it feels good. Other tracks are present to "show" the clear sound, and other low etc. ...

I would say that high frequencies are reproduced, sometimes a little too present on some pieces, but I quibble a bit. Most other headphones do not have that at high frequencies is a bit hazy, as if the very high frequency harmonics are suppressed here, they feel very (too) well.
The sound is sharp, like a magnifying glass on the various instruments it is possible to "isolate". Unlike the Senn HD595, for example, or the sound is a mixture and where it is difficult to extract the piano by ear the rest.
With the Ultrasone 750, it does so very well. This is probably due to the spatialization I think. Also, the accuracy of the sound. Unlike others who have a sound very dull, this one has no sound ... different.
In fact, opening the headphone, we notice that a metal plate with small holes qq lie in front of the HP headphones, in my opinion, I S-logic principle is that sound coming out of HP in part reflect between our ears metal and Passover, which would effect the sound spatialization but not dull, dry, but to extrapolate to death, it's like
there was the reverberation effect that fesait spatialization. Anyway, I really like the rendering.

The spectrum has a wide area. The sound is rather well reproduces from the original, but there are better among competitors.

With clarity and spatialization, we have a magnifying effect on the music, we find all the defects, we hear the singer's breath, we guess it's a synt and not a real piano so ...

Typically, I find that the Augustinian are put forward, the medium a little behind. The bass is correct, what good is that they do not puff at all the rest of the spectrum as do some headphones. But sometimes I find them a little retait on some tracks.
Beyerdynamic of daft punk and very bassy and deep. On the Ultrasone Pro 750, are present but not as they actually are. While on other tracks, it makes very good.
But overall, I find it very balanced, with crisp and pure.

I can understand you not love these headphones at all because it is a different beast from other upscale and unique, just as one can love it in sound. But one thing is for sure is that to use the studio as a "magnifying glass" on the potential flaws, this is probably the best I've ever heard.
Afterwards, an aesthetic standpoint, I find it quite ugly, plastic headphones of this price, they might make an effort. It is quite large.
The sensitivity and impedance allow playback on Walkman or iPod, but the volume will be reduced and the possibilities of the headphones will not be fully exploited (for AC amplifier required)
But I also use it in mobile mode and AC passes, finally good it is bulky and the volume reduced, but that's okay and the audio quality is at the appointment.

A big plus because the cable is removable, so the atria, it is resistant.

The pros:
sound quality: sharpness and precision
the spatialization,
the effect of "magnifying glass"
adequately covers the spectrum
strength,
removable parts,
the package.

The -:
The treble can be a bit too pronounced and the bass is better on other headphones, but it remains more than adequate in my opinion.
The appearance (plastic), size (imposing) and design.

I would put a good 9 / 10 Me.