Design and features:The headphones work with or without the noise canceling feature being turned on. You can use the noise-canceling feature without listening to music. In addition to wireless operation with Bluetooth devices, the BT 100 NC can be cord connected. In cord connected mode the earphones have high sensitivity regardless of whether the noise canceling feature is turned on or off, so they can provide satisfying volume levels when used with home audio equipment and even lower powered portable audio devices. It has an integrated microphone and built-in volume, music player function, and call connect/disconnect controls for Bluetooth paired devices. The BT 100 NC uses a collar/earphone design - all of the electronics and controls are incorporated into an open collar that sits around the neck, and the earphones are attached to wires that extend from the collar. When the earphones are not in use they can be stored in sockets at the ends of the collar. This model is claimed by the manufacturer to be water resistant, has Bluetooth NFC pairing, and comes with four pairs of ear pieces in various sizes, a detachable 40-inch long audio cable for wired use, and a USB charging cable.
Sound quality: We found the BT 100 NC provides good active noise reduction and that the sound remained the same regardless of whether it used in Bluetooth or wired mode, or whether the noise canceling feature was turned on or off. It 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. The overall sound can best be summarized as neutral (neither full nor lean), a bit washed-out, and a little rough. Bass (as in bass drums, bass guitars, stand-up bass, etc.) has good detail, goes fairly deep, and has decent impact. The midrange (voices, guitars, horns, etc.) is slightly lean and the upper midrange is a bit grainy. The treble (cymbals, the upper range of violins, etc.) is extended, but is somewhat prominent and a bit smeared - sounds that should have a delicate shimmer sound blurred. The sound 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; however, it doesn't do a good job of conveying the bass and lower midrange resonant sounds in a recording. This model provides good noise reduction overall; it excels at quieting low-pitch noise, but doesn't quiet higher-pitched noise. We also found that when the noise cancellation feature is turned on there is a very slight medium-pitched hiss that can be heard when there is no audio program material or background noise to drown it out.
Comfort: We found that these earphones fit and stay in place with no problems, and the collar is not generally noticeable and is very convenient unless it interferes with clothing. The earphones do produce sense of pressure in the ear opening might be uncomfortable for some. When the earphones are not in the user's ears they can be stored in a socket in the front of the collar; fitting the earphones in the sockets may take some fiddling.