Begin typing your search above and press return to search. Press Esc to cancel.

Ultrasone Pro 900i headphones

Ultrasone Pro 900i headphones

Ultrasone is a veteran in the personal audio community. Based in Germany, its been building high-performance headphones for over twenty-seven years. Its Edition 7, introduced in 2006, became an instant classic among headphone enthusiasts due to its highly limited production run, unique styling, and proprietary S-Logic ‘Natural Surround Sound’ and ‘Ultra Low Emission’ (ULE) mu-metal shielding technologies. 

S-Logic technology positions drive units at some distance from and at an angle to the wearers’ ears. The company has been refining this technology for years which, says the blurb, involves directing sound signals, “off the surface of the outer ear in different directions before entering the auditory canal to create a natural three-dimensional sound.” 

The Ultrasone Pro 900i is a closed-back dynamic headphone designed for in-studio use by music professionals; naturally, it also incorporates both S-Logic Plus and ULE technologies. The Pro 900i features 40mm titanium-coated Mylar drivers in a lightweight black composite frame with velvet earpads for extra cushioning. They fold flat for easy storage into an included soft-case which features two detachable cables: one 3m coiled cable with a 6.35mm Neutrik plug, the other a 1m straight cable with a 3.5mm Neutrik plug. Both offer gold-plated connectors. 

The 900i’s also come with an extra pair of velvet earpads, instantly changeable via Ultrasone’s ‘Speedy Switch’ system. These headphones are incredibly light and comfortable, weighing in at 295 grams. Their cushy extra wide headband is wrapped in artificial leather and their clamping force is light. This makes them ideal for music professionals, as they need to keep their headphones on during extended recording sessions. Their fit and feel are akin to other studio favourites such as Sony’s MDR-7506 (though the 900i is considerably lighter) and Audio Technica’s ATH-M50. Both have been popular in the music and recording industries for many years. Where the 900i stands out from the pack: soundstaging capabilities, tonal balance, and extreme comfort.

‘Before Your Very Eyes’ by Atoms for Peace [XL Recordings] is a grand display of the 900i’s penchant for the velocity of atmospheric rock-n-roll. The pounding of the kick drum slams with weight and punch, disappearing with little to no overhang. Guitars crunch, floating effortlessly in their own space. The modulating synths echo and ping back-and-forth with intense precision and speed, yet without mucking up Thom Yorke’s soaring vocals. This is a dark track, but its musical mood switches from light to dark like a fluorescent light-bulb. Some headphones mask this yin-yang effect, but the 900i nails it. The uniquely alien character of Yorke’s vocal is also well-preserved and reproduced. This track showcases the 900i’s impressive transparency and accuracy. The low bass may seem a bit lean at times, but that could be because competing headphones so often ‘goose up’ the low-end. 

The 900i proves equally capable in its handling of Tori Amos’s vocals on ‘Wild Way’ from Unrepentant Geraldines [Mercury Classics]. Amos’s pained delivery is emotively charged and breathy. The Pro 900i captures the wispy, seductive quality of Amos’s voice and with it the intense duality of emotion she conveys. If a headphone’s resolving capabilities are not up to par, Tori’s voice tends to sound too chesty, losing key subtleties and nuances. The 900i’s show Amos’ voice is warm and vibrant, but not overly-so, so that Amos’ voice sounds at once beautiful and torn. The 900i’s also do a splendid job with her piano and minimal string arrangements. The instruments bob and weave without getting congested. 

Ultrasone has produced a solid all-around performer with the Pro 900i. The headphone’s amazingly lightweight and comfortable feel make it a terrific choice for musicians, industry professionals, and personal audio devotees looking for a lightweight, closed-back dynamic that’s great for use on airplanes and in the recording studio. At €469/$499, the Pro 900i should please artists and portable audiophiles alike.


Ultrasone Pro 900i headphones

Type: closed back, circumaural dynamic headphones

Driver Type: 40mm titanium-coated Mylar dynamic drivers

Magnets: NdFeB

Sensitivity: 96dB

Impedance: 40 Ohms

Frequency Response: 6Hz–42kHz

Weight: 295g, excluding cables

Provided cable type: detachable gold-plated (one 1 metre 1/4” Neutrik, one three-metre coiled 3.5mm Neutrik)

Accessories: One pair Velvet ‘Speed Switch’ earpads 

Price: $499, €469


Ultrasone AG

Tutzing, Germany

Phone: +49 (0) 881 901150 0




By Michael Mercer

More articles from this author

Read Next From Review

See all
Franc Audio Accessories Ceramic Disc Isolator feet

Franc Audio Accessories Ceramic Disc Isolator feet

Feet don't fail me now! Clever isolation feet from Franc Audio use ceramic to isolate your components from the world entire, according to Jason Kennedy.

Davone Meander all-in-one system

Davone Meander all-in-one system

Classic Scandinavian design and clever, innovative all-in-one streaming technology... what's not to like?

Thales TTT-Slim II, Simplicity II, X-quisite CA turntable, arm and cartridge

Thales TTT-Slim II, Simplicity II, X-quisite CA turntable, arm and cartridge

With a battery-driven turntable and clever tracking pivoted arm, Swiss turntable brand Thales is one of the hidden treasures of audio.

PrimaLuna Evo 400 integrated amplifier

PrimaLuna Evo 400 integrated amplifier

PrimaLuna represents a fine mix of high-end audio and pure-valve performance without stratospheric pricing, but does the top integrated amp in the company's popular EVO line cut the musical mustard?

Sign Up To Our Newsletter