Ultrasone HFI-2400 Review


  • Tight, punchy bass
  • Very Dynamic
  • Solid, high-quality construction
  • Extremely comfortable


Our Score 8.5
User Score 0


  • Open-backed design doesn’t provide sound isolation
  • No 1/8” adapter provided
  • Require precise positioning for the best sound
Move over, Sennheiser. Ultrasone’s HFI-2400 combine the best of German design with a price tag we can live with.


Ultrasone is a relative newcomer to the U.S. headphone market. Founded in 1991 and based in Tutzing Germany, Ultrasone has provided the European market with products for the past 19 years. Fortunately for us, the brand is beginning to catch some mainstream attention here in the U.S. and, if they keep making products like the HFI-2400, we think that trend will continue upward. Ultrasone doesn’t tip-toe around the notion that there is more than one German high-end headphone maker (Sennheiser, are your ears burning?) and makes some pretty bold claims as to being “THE German Headphone Company”. In our review of the HFI-2400, we find out if Ultrasone’s bravado translates to hot sound or just a bunch of hot air.

Out of the Box

The HFI-2400 comes with a minimum of packaging fluff. Inside the unassuming box we found the HFI-2400, the headphone’s detachable cable, a demo CD, an instruction manual and a black velvet carrying and storage pouch.

The HFI-2400’s robust construction makes them appear as if they will be fairly heavy but at just 10 ounces (292 grams) the headphones turn out to be reasonably light. The black headband is wide and sturdy with strategically placed padding and oversized hinges that secure it to the individual earphones. The earphones are made of black and grey plastic with a shiny aluminum plate decoratively placed in the center of the earphone’s backing. The inside of the earphone includes foam earpads covered in black velvet cloth.

The HFI-2400’s detachable 3m cord connects at the base of the left earphone. The headphones swivel inward 90 degrees and can swivel up another 90 degrees for more compact storage. Ultrasone clearly indicates which side is which on both the earphone’s back-plates and hinges.

Features and Design

The HFI-2400 headphones are packing a few proprietary designs that are worth noting: Ultrasone’s patented S-Logic Natural Surround Sound doesn’t rely on complicated digital processing or any other electronic wizardry to achieve a surround sound effect. Instead, Ultrasone uses “decentralized driver positioning” to achieve a natural surround feel. The idea is that by directing sound at several parts of your ear (not just dead center) what you hear will seem to come from all around your head and not just in your head. We took off the easily removable ear pads to have a look at the drivers. Indeed, rather than place the drivers in the center of the earphone, Ultrasone has positioned them at the 5:00 position. This decentralized driver positioning means that the user must put the headphones on correctly. When reversed, there is a noticeable and unflattering change in the upper midrange and treble response.

Ultrasone also makes a big deal about their Ultra Low Emission (ULE) electro-magnetic shielding. Apparently, wearing headphones for long periods of time exposes us to electro-magnetic radiation that can be hazardous to our health. To keep us safe, Ultrasone has implemented magnetic shielding that reduces the electro-magnetic field emission by 98%. We’re not sure how helpful this shielding is in the long run, but the placement of a large metal plate over the bulk of the driver section did not seem to negatively affect the HFI-2400’s performance. Though we’re not sure how beneficial this shielding actually is, we’re pleased that it didn’t adversely affect the sound quality.

Ultrasone may lay it on a little thick with the marketing gems but the HFI-2400 really is a well conceived set of headphones. They are extremely comfortable and rest securely on the head without creating un-needed pressure on the areas around the ear. The velvet cushions do a great job of keeping things cool and dry over long listening sessions. The long, 10 foot cord screws into the base of the earphones for a very secure connection and is strong enough to withstand an above average amount of abuse. The stout hinges allow for the ‘phones to be collapsed down for more compact storage and transport. In fact, after handling the HFI-2400 for a couple of weeks we were left believing that this set of cans will hold up in the long term..

Positioned at the top of Ultrasone’s HFI line, the 2400 have the look and feel of a high-end headphone, but lack some of the accessories that we’ve come to expect from a top-of-the-line offering. Our guess is that Ultrasone has chosen to leave some of these perks out of their HFI line in order to make these ‘phones more affordable and, if that is the case, we applaud them. Those fancy extras are available in the more expensive PRO line for those that will make practical use out of such extras as a hard case, coiled and straight cords and alternate earpad materials. To have the same guts as the more expensive PRO line without the extra cost involved shows careful consideration of the customer’s need and that’s something that we can all appreciate.

Our only complaint about the HFI-2400 is that, at this price level, we still expect to see an audio adapter that allows the HFI-2400’s large ¼” plug to be downsized to suit an iPod, laptop or other portable audio/video device. While this sort of adapter comes cheap at most electronic stores, we hope for something that is on par with the quality of the headphones themselves.

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