Panasonic RP-HC500

Noise-cancelling headphones work by creating "anti-noise" that exactly counterbalances external sounds at the ear.  While unable to cope with non-repetitive sounds, they do a good job of reducing the constant drone in an airliner cabin or the hum of a room air conditioner or computer fan.

  Noise-cancelling headphones began as an expensive, bulky laboratory concept, but with an MSRP of under $200, Panasonic's top-of-the-line RP-HC500 puts them within reach.  Neodymium magnets backing large 1.56" drivers, a gold-plated connector, and a frequency response of 8 Hz to 22 KHz attest to Panasonic's attention to quality.  Noise-cancelling headphones aren't intended to stay in a listening room almost by definition, so a fold-flat design, carrying pouch, aircraft adapter, and detachable cord are all included.  The RP-HC500 provides 22 dB of noise reduction at 200 Hz for up to 40 hours on a single AAA alkaline battery.