YOU’LL NEVER BE TEMPTED to take this headphone on the bus. The earpieces of Audio-Technica’s ATH-AD900 are huge, measuring about 4.5 inches in diameter and concealing a big 53mm driver. Unlike almost all other headphones, the ATH-AD900 does not have an adjustable band. Instead, it features a pair of spring-loaded, padded “wings” that support it on your head. The soft padding and big earcups made the ATH-AD900 super-comfortable for Howard, Joe, and me. But it felt droopy to Will, and Geoff found the feel of the wings on his bald pate intolerable after a few minutes.
The two oldest panelists — Howard and I — especially loved the sound of the ATH-AD900, and the younger panelists liked it pretty well, too. Howard picked it as his favorite. “It has a virtually perfect balance, very clean and open-sounding,” he raved. Will ranked it last, but still enjoyed the sound. During the couple of weeks I spent putting this article together, I found myself grabbing the ATH-AD900 most often when I wanted to listen for fun — partly for the comfort but mostly for the performance.
Everyone felt the ATH-AD900 had a spacious, involving ambience, but most of the panelists also felt its bass was a little weak. This isn’t a great headphone for rock music; when I played Mötley Crüe’s “Kickstart My Heart,” Tommy Lee’s powerful kick drum practically vanished from the mix. Some complained that the treble sounded a bit overemphasized, which occasionally made voices sound harsh.
The frequency response of the ATH-AD900 confirms our listeners’ impressions that its tonal balance is light on the bass and perhaps a tad trebly. Driving it from a 75-ohm output impedance produced only a slight change in frequency response, a bump of about 1 dB centered around 100 Hz. Impedance averages about 35 ohms at most frequencies, except for an increase to 45 ohms in a broad band centered at 90 Hz. The ATH-AD900 offers little isolation — no surprise for a large open-back headphone. Distortion is low at 80 dB; at 100 dB, it rises below 70 Hz to 15.7% at 20 Hz. Average sensitivity from 300 Hz to 10 kHz with a 0.179-volt RMS signal is 104.4 dB.
If the unusual fit of the ATH-AD900 suits your head, and its bass-shy balance suits your taste in music, this headphone is a fantastic bargain: I noticed it selling for just a tad under $200 from some Internet dealers.