Our experience with the HFI-2400 was particularly interesting because, more than any other headphone we’ve tested, the performance of the Ultrasones seemed to change for the better the more we used them. Those that believe strongly in providing a break-in period for all things speaker-related will find that the HFI-2400 benefit a great deal from some pre-evaluation use. Straight out of the box, the high frequency response was extremely hot. It was enough to make us want to remove the HFI-2400 and come back to them later. After about 45 hours of use, however, the HFI-2400’s sound signature changed significantly and for the better.
We love the deep, punchy, super accurate bass response of the HFI-2400’s straight out of the box. While we expected some hearty bass from a headphone of this size, we were pleasantly surprised at how immediate and articulate the 2400’s bass response was. When we listened to Jimmy Smith’s organ on “S Wonderful” from The Sermon we could feel the weight of each key being struck as if we were sitting right next to Jimmy’s leslie speaker. The bass was naturally resonant and never over-bloated as we’ve often heard in other high-end headphones. For something more modern, we pulled up Sheryl Crow’s “Steve McQueen” from her C’mon C’mon album. This track has the drums front and center in a sort of super-produced way. Over-produced as it may be, the ultra-big bass at the top of the tune makes for a good test of low end capability and the HFI-2400 did not disappoint. We got all of the big bass that the recording engineer intended but no more. In fact, it was a little like jumping behind the scenes in the recording studio and getting some insight into what the engineer’s intent must have been.
Fortunately, the Ultrasone’s are not a one trick pony. Many large, over the ear headphones deliver mind-pounding bass but fall short on midrange and treble accuracy. Such is not the case with the HFI-2400. Their midrange response was extremely appealing and open and had a warmth to it that we found to be on par with headphones that cost 5 times as much. Listening to Michael Buble’s “Feeling Good” from the It’s Time album through the 2400’s was an unexpected treat. Buble’s sculpted vocals came across with stunning clarity and accuracy. To get any closer to the real thing would have required having Buble’ himself sing directly into our ear.
High frequency response, initially, was a concern. For all that the HFI-2400 did well, we couldn’t get over how metallic the extreme high frequencies sounded. Fortunately, the aforementioned break-in period tamed this unwelcome attribute and really evened out the sound. Once broken in, the HFI-2400 reproduced incredible inner detail, texture and air around all of the high frequencies. Rather than sounding sterile, the highs now brought realism to the sound that we simply didn’t expect from a headphone at this price point. The only down side to this intense high frequency response is that it exposes compressed music files for all of their limitations. When listening to compressed versions of our test cuts the raspy, digital edges around the high frequencies were exacerbated to an embarrassing degree and the upper midrange was compromised as well. Once natural vocals now sounded squashed and honky by comparison.
We tested the HFI-2400 with an iPhone, iPod Touch, Dell Laptop Computer, Onkyo and Harman Kardon receivers and through a HeadRoom DAC and Amp combo. As one would expect: the better the source, the better the sound. But the delta between the good and the bad was more sharply pronounced with the HFI-2400 than almost any headphone we’ve reviewed to date. They hide nothing, so be prepared to hear just how bad (or good) your computer’s sound card or iPod really is.
We have only a few criticisms to offer in regard to the performance of the HFI-2400 by Ultrasone: As open backed headphones, these are not great at keeping outside noise from bleeding in nor are they adept at protecting your neighbors from enjoying your musical selections. However, we feel that this trade-off is worth their exceptional performance. Just know that you’re better off enjoying these cans in the privacy of your home or office than on the bus or in your local coffee shop.
The Ultrasone HFI-2400 sound incredible and, at $299.00, they outperform headphones that cost much more. Their balanced, engaging response and tremendous dynamic capability are the stuff that audiophiles drool over. We found them extremely entertaining and satisfying. We would encourage you to give the HFI-2400 a listen and consider putting the money saved into a headphone amp to raise them to their full potential. The return on investment here is very much in the listener’s favor. Highly recommended!
- Tight, punchy bass
- Very Dyanamic
- Solid, high-quality construction
- Extremely comfortable
- Open-backed design doesn’t provide sound isolation
- No 1/8” adapter provided
- Require precise positioning for the best sound