The Ultrasone HFI 680s sit squarely in the middle of the HFI range from Ultrasone. According to Ultrasone, they are the natural and balanced closed option in the HFI range. On either side is the HFI 580 (easier to drive and with a bigger bass punch) and the HFI 780 (also easier to drive and with a more dynamic sound designed for movies and gaming). For me, it was all about natural sound reproduction so after many auditions (thank you again to George and the team at Addicted to Audio) I chose the HFI 680s.
The HFI 680s are a closed headphone that isolate quite well from the outside world. With music playing, only loud sounds are noticeable and others around you won’t hear your tunes.
Out of the box, the 680s actually impressed me with their build quality. My initial impressions during auditioning weren’t great, but perhaps that’s because they weren’t new. Having appreciated the phones brand new, I am now more aware of the build quality, which is better than average, but mostly plastic. The headband has good flexibility and the phones fold up really nicely to fit inside a plush Ultrasone branded pouch that comes with them. There is a soft, pleather covered memory-foam pad under the headband which is quite comfortable for relatively long periods, but I find after about 1.5-2 hours I need to readjust where the pad is touching my head because of minor pressure pain. The pleather covered cups are very comfortable for long periods and clamping pressure is also fine. Of course, there’s some minor sweat build-up as a result of the pleather, but it’s the only way to get a good seal.
The 680s come with a 3m cable which is great for sitting in your favourite chair away from the stereo or TV, but it’s not so good for portable listening. A minor issue though that’s easily fixed with a velcro cable tidy.
The other inclusion in the package with the 680s is the Ultrasone demo disc. This disc is full of amazing recordings to hear what your headphones (Ultrasone or other brands) are capable of, but it’s mostly not music I would listen to for fun. That said it was fun to see how my new Ultrasones matched up against my existing phones and speakers.
Important note: this review is conducted using the 680s from an amplified source (in this case my Creative Sound Blaster X-Fi HD). They perform well from my iPod Video (5.5G), but struggled to have the same open, magical sound when driven by just my laptop. These headphones need a good source behind them so ensure that you test them thoroughly with your source player if it’s not amplified. Some portables will be fine while others will sound very ordinary through the 680s.
Speaker Driver: 40mm
Frequency Range: 15 – 25,000 Hz
Impedance: 75 ohms (can be a bit tricky to drive for some portable devices and computers)
Attack: The attack from the 680s is excellent. They have great punch and good control. One of the benefits of high impedance headphones/speakers is improved control and the 680s definitely show this with their precision attack. My favourite bass test, “Take the Lord Along with You” by Wayman Tisdale had the 680s really dancing to all of the slap bass and they handled it beautifully with plenty of punch and feeling, but no real muddiness. On tracks with big, consistent bass, the 680s can start to sound a little bloated in comparison to more delicate headphones like the ATH-AD900s, but they are excellent bass performers for the dollars and make up for any slight looseness with their power and presence. While both the HFI-680s and AD900s have good bass attack (the AD900s slightly better controlled), the 680s come out sounding a fraction better here because of the extra punch behind the bass which I’ll discuss next.
Rating: 8.5 / 10
Mass: The mass from the 680s is truly impressive. Your ears feel the bass just like your whole body would in a live concert. At times I fell like they overplay the bass just a fraction, but it’s fun and doesn’t detract from the quality of the sound. Listening to Also Saprach Zarathustra from the Ultrasone demo disc, the deep rumble from the pipe organ felt as good as it sounded, but some other tracks can get a bit uncomfortable because of the pressure created. It’s a double-edged sword. I love the feeling of the bass, but every now and then it gets a bit much. This is probably more a reflection of different recording and production values more than a fault of the headphones though so I’d still recommend the 680s for their overall bass style – it’s fun, lively and exciting.
Rating: 9 / 10
Vocals / Mids
The vocals and mids are rich and warm from the 680s. Not as warm as a headphone like the Shure SRH840, but still very cosy. The detail is there, but it’s a warm kind of detail. Very easy to listen to and never too forward.
Many closed headphones get a bit “canned” in the midrange. You can hear that you’re listening to a speaker in a cup, but the 680s avoid this completely. There’s no sense of that internal resonance and the sounds often extend beyond the physical boundaries of your head and ears.
Listening to Jette Torp’s voice in “Only a Woman’s Heart”, Joshua Redman’s sax in “Can a Good Thing Last Forever” and Ian Moss’ guitar and vocals in the acoustic version of “Thunderball”, all midrange instruments sounded realistic, beautifully present and silky smooth. The sound isn’t as airy as the AD900s I mentioned before, but it’s beautiful in it’s own way – smoother and a touch more mellow, but in no way lacking in detail or clarity.
Rating: 7.5 / 10
Detail & Staging
I’m combining these 2 categories for this review because they are directly related in the case of the 680s and I believe it all comes down to the fact that they’re a closed headphone. The 680s have a very natural sound and that allows each individual instrument and texture in the music to play out the way it’s meant to. The detail they create is beautiful and lively. There could be just a fraction of masking created by the bass produced by the 680s, but if so it’s only minor. It could just be that they’re a little bit warmer and the fuller sound takes your attention elsewhere in the music (away from the top-end detail), but the simple fact that I can’t quite explain where the difference lies should give you a good idea that it’s very subtle and not a problem at all.
Ultrasone use a technique called S-Logic which directs the sound to your outer ear (the flappy bit) so it can enter your ear like live sounds do rather than being played directly into the ear canal. Whether it’s this technology or something else, the 680s are a very convincing closed headphone. The sounds often seem to be coming from somewhere beyond the side of your head and the imaging is outstanding. Closing your eyes with the 680s playing, you can easily picture where each instrument was being played and sometimes you can even pick the size and shape of the room or the crowd.
The only thing that holds the 680s back is a fractional lack of detail at the very top end and just a hint of harshness at times. In both cases I’m comparing the 680s to other options that excel in detail (like the AD900s) so, again, it’s a very minor issue. With the 680s, I hear 98% of all of the sounds in the music with harshness 5% of the time. With the AD900s I hear 99% of the sounds and experience harshness about 2% of the time. It’s a tiny difference and well worth the sacrifice for those times that I want extra bass or need to keep my music to myself.
Rating: 7 / 10
I did a lot of auditioning and listening before deciding on the HFI 680s and I can honestly say I haven’t experienced even a moment of buyer’s remorse. These headphones are another example of truly great value for money (they retail for around AUD $300). There are better headphones out there, but not for the price. Having listened to similar priced alternatives from Shure, Audio-Technica, Sennheiser and Beyer-Dynamic, the 680s came out clear winners.
Like many good headphones or speakers, they really shine (and I mean REALLY) when given a good source player and some good music. If you have an amp or a high quality output device like a full size iPod or hi-end player from companies like Cowon, HiFi Man, etc. you will really enjoy these headphones. To get better sound, you’ll be spending a lot more money!
I feel like I haven’t described enough about the sound of the 680s in this review, but, on reflection, I think that’s as much a testament to their balanced, natural sound as anything else. Nothing about the 680s stands out over anything else and that’s a good attribute for a set of headphones. They’re not exactly neutral, but they’re well balanced across the spectrum. The 680s are fun, exciting and realistic – everything you want with nothing you don’t.
Overall Rating: 7.5 / 10