Harman subsidiary AKG has been in the business of making personal and professional audio equipment since the 1940s, so one might rightfully expect top-notch quality from the company's line of headphones and earphones, of which there are plenty to choose from. The latest offering, set to hit the States in October, is the AKG K390 Infinity Noise-Canceling earphones. This in-ear model features a double-whammy of passive sound isolation and active noise cancellation, making it a tempting option for commuters and frequent fliers. But at $249, these earphones are far from cheap, and buyers should be wary of potential fit issues, as comfort is key for any extended-wear scenarios.
The AKG K390 earphones have a sleek, understated design that leans toward darker hues with matte black and shiny gunmetal plastics comprising the earpieces, cable, and noise cancellation module. The earbuds are slightly larger than average and feature an external port (for more airflow, we assume) and a reinforced cable connection for durability. Like the 'buds, the sound apertures are on the large side, which caused some discomfort for us during testing no matter which eartips we used. About halfway down the cord descending from the right earpiece, you'll find the integrated mic and call answer button--a handy feature for music phone users. This first segment of cable measures about a foot and a half long before joining with the noise cancellation unit.
There's no getting around the fact that the K390's noise cancellation module is rather hefty in both size and weight. Luckily, AKG built in a shirt clip to alleviate concerns raised by the latter (so the earbuds are not pulled out of the ear by the weight). However, the module measures almost 3 inches across and it's an inch tall and a bit more than 0.5 inch deep, so it's definitely not the most inconspicuous thing to have attached on your person. The top edge of the unit houses an on/off switch for the noise-canceling feature as well as a mute button that allows you to hear what's going on around you without removing the earbuds. A single AAA battery is concealed beneath a flap on the bottom side. This is also where you attach the included stereo patch cable for connecting your MP3 player or other audio source. It's nice that the cord is detachable as this provides a more clutter-free method for utilizing the noise cancellation as a standalone feature (on an airplane, for example).
As mentioned, AKG has been in the audio game a long time, so we went into the K390's testing with high expectations. Overall, we were pretty impressed by the sound offered up by the earphones, particularly the fact that it changed very little based on whether noise cancellation was activated. The K390s manage to put forth a nice, crisp response with plenty of detail on the high-end, yet they were not too bright for our tastes. Mids weren't as remarkable; though music sounded reasonably warm, it wasn't quite as rich or buttery as we like. Bass response was a bit of a mixed bag. On the one hand--if you can get a good seal with the ear--the lows are nice and tight without being overwhelming, but once you turn on the noise cancellation, the low-end loses a bit of its "oomph." Picky listeners, however, may be able to find more suitable options.