Pros: razor-sharp clarity, bright, balanced sound signature, comfort, packaging and accessories
Cons: really, REALLY bright; expensive, can be quite harsh, heavily source and amp dependent
As the Ultrasone Pro 750 arrived, I really wanted to like them. After all, these headphones embody just about everything I've claimed to like in the past few months of acquisition and experimentation with various headphones. They have a very balanced sound signature, they are detailed, and bright rather than dark. I was waiting for that Ultrasone bass that I kept hearing about, and I was prepared to give them enough time to really get a sense of them.
Well, it's been over a week, and I've put quite a few hours on the 750s. Do I like them? I'm still not sure. There are a lot of things I like about them, but there are some troubling areas as well.
I really like the build quality and packaging. It's great to have a choice between the coiled and straight cord, the headphones themselves are well-built without feeling bulky, I find I can wear them comfortably for hours, they have the right amount of clamping pressure, and the replacement pads are a nice touch. The hard case will definitely keep them safe when not in use, and I'd really like to see more companies include a good transportation option.
On a first listen, though, I was a lot less impressed. As I've already said, I like bright headphones. I got rid of the Shure SRH-840 because I found them bland. I like the Beyer DT-990 Pros and never found them too harsh. None of this prepared me for the sharpness that is Ultrasone treble. My first impression was that sharp glass was being jammed into my ears. I gave them some time, because I knew it might just need some further breaking in or that perhaps I would just need to spend some time getting used to the overall sound signature. For a few days, I kept trying, and was getting increasingly frustrated. I couldn't begin to understand why anyone would like this sound.
One afternoon, I was in the basement with my laptop, and I didn't have my usual amp setup--just my humble Hotaudio Bitperfect. Although it's not the best amp in my inventory, it is significantly warmer than my other sources, and it made a huge difference. The warmth of this amp cut the edge off the treble, and brought a bit of warmth to the midrange. Suddenly, the 750's sound signature started to make a bit more sense. The rest of the review is written as the headphones sound out of a warm source. I still can't listen to these cans out of my custom DAC/Amp, which sounds better for all of my other headphones.
There's no question, these are still treble-heavy cans. What consistently impresses me is their detail retrieval. Even when stacked up against the DT990/600, the DT150, and Fostex T50RP, the Ultrasones consistently reveal details that the other headphones obscure. I've never heard cymbals like this, and they create a truly impressive feeling of sparkle and space around instruments and vocalists. When I use Massive Attack's Angel as a test track, it's always the bass that stands out. With the Pro 750, the bass is there, but what really stands out is the clarity and punch of the drums. That clarity and punch is true of other instruments as well. I used to play trombone in jazz bands, which means I stood right in front of rows of trumpets. Loading up tracks like The Mingus Big Band's Wednesday Night Prayer Meeting reminded me exactly how that used to sound. They make trumpets and alto saxes sound spectacular. These are hugely energetic headphones.
Detractors of the Ultrasone sound always talk about the metallic midrange, and it's a fair criticism. That brightness that creates such clarity and punch in the high end also draws warmth out of the midrange, where it's needed most. Jeff Buckley's Lilac Wine is one of my other test tracks, and while the Ultrasones do a great job of creating space between the instruments, it doesn't showcase his voice as well as some of my other headphones. This is a bigger problem for female vocals. Fiona Apple's voice should sound rich and warm, not sharp. Ironically, what isn't perfect for vocals proves to be excellent with both piano and guitar, though, and it makes me wonder if I'm not just used to warmth being added by most headphones.
The Pro 750s have exceptional bass, but it's also very balanced. That means these are definitely not the Ultrasones to recommend to serious bassheads. In tracks with lots of bass, the Pro 750 delivers with ease, diving as deep as the track demands. They lack the muscle of the Beyerdynamics at the bottom end, but deliver some of the tightest bass I've heard. Even with low electronic bass, individual notes are always clear. They pass both the Angel test and The Chemical Brothers' Under the Influence test with ease. Still, with both these tracks, by the time the bass is up where I want it to be, I find myself overwhelmed by the bright treble. The bass is a reminder that these are meant to be studio tools, not DJ headphones and not for casual listening.
The other big question with Ultrasones is whether or not the S-Logic works. For me, the answer is "sort of". The effect is surprisingly subtle, and does place the sound slightly outside the skull, but certainly doesn't perform any magic. I think people go in expecting the S-Logic to live up to the marketing hype, and it really doesn't. It's just another way to create a slightly more open sound from a closed pair of headphones.
I have a few other things I want to make sure make it into this review for people who are curious about the 750. First, their ability to resolve detail makes them extremely source-dependent. They sound like total crap on tracks that were poorly mastered, and they reveal compression in low-bitrate MP3s better than any other pair of headphones I've ever put on. These are a bad choice for anyone who is unwilling to commit to seeking out high quality copies of well-mastered music. Pop music that suffers from the loudness wars are particularly painful--keep these headphones far away from contemporary radio pop.
In addition to being source-dependant, I've already pointed out that they are quite amp-dependant. They sound unbearable out of my custom DAC/Amp, unpleasant out of my Cute Battery II, and completely wrong out of the Musical Paradise tube amp. I had high hopes for that combination because of the warmth of the tubes, but no luck. They sound better from my Yamaha Home Theatre receiver, but best out of the Hotaudio Bitperfect, which I can't say is true of any of the other cans I own. I also usually hate software sound modification. I almost never use equalizers, dislike crossfeed effects, and always find software virtualization just muddies up the sound. Strangely enough, I find that the Izotope Ozone plugin for Winamp really improves the overall tone of the Pro 750s, which means they respond quite well to equalization. I'd be interested to know what percentage of Ultrasone owners use software mods compared to fans of other brands.
They also don't isolate particularly well for closed headphones. Even at moderate listening levels, these leak quite a bit of noise, especially when taken off. They don't leak as much as Grados, of course, but I wouldn't use these if you need to wear headphones next to someone that's trying to sleep.
Again, the Pro 750s make for a tough recommendation. It's taken a week, but I am starting to hear what makes these headphones so polarizing. I understand why Ultrasone spawns rabid fanboy enthusiasm, because I've never heard clarity quite like this, especially from dynamic headphones. They are bold, brash and uncompromising, and I suspect that getting too used to this sound would spoil you for most other brands. I also understand why some people have described these as the worst headphones they've ever heard. They are sharp and icy cold, and I find they take getting used to every time I've been listening to other headphones. After listening to them for an hour, though, they make most of my other headphones sound muddy and flabby, which is actually pretty impressive. I'm not trying to say that either side of this debate is right, but I will say that we won't see this argument go away any time soon.
For now, I'm going to hang on to the 750s. They do some things stunningly well, and even though they are never easy headphones to listen to, they are magical with certain tracks. I'm not sure yet whether they will be a permanent addition to my collection, but I at least admire how uncompromising Ultrasone were when they designed these. Will you like them? Your guess is as good as mine. Do everything you can to hear a pair before you drop the money on them, though, because there are definitely no guarantees.
I am doing a quick follow-up. Last week, I completed the well-documented Kees mod on the Ultrasone Pro 750, and I'm pleased to say it has made an absolute world of difference. The bass has been brought out a bit, the mids have been sweetened, and it tamed the highs nicely. They are still very cold headphones, but are now genuinely enjoyable with almost every track I've tried them with. They have maintained their analytical qualities and balance, and could now be used for professional monitoring and mixing if needed. Because of the ease of modding these, I have adjusted my score accordingly.