Design and features:0
Sound quality:We found the Live 660NC delivers sound quality that falls in the very good range - it reproduces music and voice very well although it does have some noticeable sonic quirks and excellent active noise reduction. With the noise cancelling mode engaged and the JBL Headphone app tone settings set to off, and the Smart Audio Mode set to Audio Mode (as received state of the headphone) the bass (as in bass drums, bass guitars, stand-up bass, etc.) has good impact and goes deep, but is slightly prominent and somewhat boomy. The midrange (voices, guitars, horns, etc.) is fairly even, but is slightly hazy, grainy, and congested, a touch etched (a bit more sharply outlined then it should be), and depending on the program material can be a bit crowded by the bass. The treble (cymbals, the upper range of violins, etc.) is extended but is a bit smeared and sizzly (sounds that should have a delicate shimmer have a sound reminiscent of bacon frying). The sound also has a good sense of liveliness and is somewhat open--sound-wise it almost seems like you don't have anything plugging up your ears and does a decent job of recovering room ambience. Warmish character. The overall sound can best be summarized as a somewhat bassy and a bit grainy. The tone settings of the app do have a noticeable effect on the sound of these headphones. When cord connected to AC powered devices may produce a noticeable hissing or humming noise when the noise canceling feature is engaged (no hum when NC is off or with portable devices that are not connected to a charger. Noise Canceling: Excellent noise reduction across the entire frequency range with the low frequencies reduced the most. Orientation changes the noise reduction characteristic - when the noise is coming from the front a bit more high-frequency noise can be heard. A faint rushing sound can be heard in quiet environments when there is no audio program to drown it out.
Comfort and Fit:We found that these headphones produce a sense of moderate pressure around the ears.
As typical of over-ear models the ear pads might feel hot and/or sticky after prolonged use.
Large
Users with larger ears might find that the over-the-ear fit of the ear pads feel cramped, or that the ear pads sit on, rather than around their ears; in that case the less-than-ideal fit around the ears might interfere with the earpad seal and reduce the noise reduction capabilities of the headphone.
Users with larger heads might find that the headband does not have enough adjustment range to allow the earcups rest properly on the ears and/or that the headband presses uncomfortably on the top of the head.
Other noise
When wearing this model while walking the muffled vibrations from each foot step can be heard through the headphones.
When the audio cord is used the sound of it rubbing on clothing may be heard through the headphones.
