Finding a really good pair of on-ear headphones can be a challenge. While they're more compact than over-the-ear models, they often aren't as comfortable -- they sit on your ear after all -- and don't measure up sound-wise to their over-the-ear brethren, which also tend to do a better job sealing out ambient noise (at least the closed-back models do anyway). So it's easy to get excited when you come across an on-ear headphone like the Beyerdynamic T 51 p that not only features top-notch sound but is sturdily built and comfortable to wear.
Made in Germany, the $289 T 51 p is a dead ringer for Beyerdynamic's earlier T 50 (now discounted to $199), but the newer model has upgraded innards and sound. The lightweight (174 grams) mostly metal design doesn't have a hinged headband, but the ear cups fold flat for easy storage in the supplied, well-designed carrying case.
If you're looking for a headphone that has an inline remote and microphone, Beyerdynamic makes the T51i, which has a 3-button Apple remote control and microphone (that model costs about $10 more). However, this "p" version is intended for the serious audiophile who doesn't want to ever lose focus on the music. Impedance is rated at a highish 60 ohms, but the T 51 p sounded great plugged into both mobile devices (iPod Classic, iPhone 5S, and Samsung Galaxy S4) and a Schiit Asgard 2 headphone amp at home.
The earcups are padded with memory foam and they sit your ears snugly without applying too much pressure. The headband conforms to your head nicely and doesn't leave a big gap in the temple region like a lot of headphones do. It's a comfortable headphone to wear for hours at a time without experiencing listening fatigue. That said, the cold metal design isn't for everyone and those with larger heads may end up with the metal part of the headband resting too close to their heads for comfort.
Isolation from external noise on the New York City subway was decent, though not up to the standards set by noise-canceling headphones and some over-the-ear models. Then again, the T 51 p sounds better than any of those headphones and it doesn't need batteries (all noise-canceling headphones do). While most audiophile headphones come with one-year warranties, the T 51 p's runs two years.
The sound balance is slightly warmer than neutral, but detail and resolution are excellent. We found it pretty versatile -- it doesn't lend itself to one genre of music over another -- and for such a compact headphone its bass is surprisingly robust. It's not overdone or thick, but if you crave a rich low-end the T 51 p won't disappoint.
Brian Eno's ambient recording, "On Land," had a wide-open spacious quality, and it sounded nearly as big as we've heard from larger open-backed headphones like the Hifiman HE-400.
We put it up against Bowers & Wilkins' similarly priced
Moving on to the Kronos Quartet, the T 51 p had just the right balance of acoustic warmth and clarity. The P5 sounded nearly as good, with just a tiny bit less body to the sound of the instruments. Both headphones are comfy, but since the T 51 p's round ear pads don't contact as much of your outer ears as the P5's flat pads, the T 51 p is less likely to make your ears sweat in hot weather.
The T 51 p also came out on top against the $349 Phonon SMB-02, another closed-back headphone that's getting a lot of buzz in audiophile circle. The SMB-02 plastic construction looks cheap next to the mostly metal T 51 p, and the bass punch pulsing through the Nine Inch Nails "Hesitation Marks" CD evaporated over the SMB-02s. Switching between the two headphones the T51p sounded considerably more natural and full.
In out next comparison, we put it up against the Sennheiser Momentum, one of our favorite over-the-ear models in this price range (the Momentum costs $60 more). In terms of sound, the T 51 p didn't quite measure up -- the Momentum has a bit warmer sound and bit wider soundstage. Also, the Momentum's cord is detachable and comes with a second cord with a built-in remote/microphone. But we did think the T 51 p was more comfortable for longer listening sessions.
Stepping down to the smaller Momentum On Ear ($199.95), the T51p came out ahead, delivering slightly richer sound and once again coming across as more present and immediate sounding. Of course, sound is a matter of taste, and T 51 p's sound profile won't appeal to everyone (editor Ty Pendlebury, for example, found its sound a touch cold for his tastes).
This is a compact audiophile headphone that's well-built and delivers top-notch sound. Its design may not be for everyone, but it is comfortable and eye-catching. For better or worse, it doesn't have an inline remote/microphone (some people won't care, others looking for a day-to-day headphone to use with their smartphone may wish it had this feature), but other than that small gripe, the T 51 p is one the best on-ear headphones we've tested in a while.
Editors' note (June 13, 2014): The rating on this product has been updated (raised from 4 stars to 4.5 stars) to reflect changes in the competitive landscape.