Koss Quiet Zone QZ PRO Noise-Canceling Over-Ear Headphones

The Koss Quiet Zone QZ PRO Noise-Canceling Over-Ear Headphones features both active and passive noise cancellation. For passive noise reduction, the QZ PRO features soft leatherette cushions, which create a tight seal around the ear and reduce ambient noise. Active noise cancellation circuitry uses tiny microphones that sample surrounding noise and transmit that information to a processing circuit, which counteracts the unwanted noise to create a quiet listening environment. Two AAA batteries are required for active noise cancellation and the noise-cancelation feature can be easily turned off with the flick of a switch. The Koss QZ PRO delivers a frequency response of 40 Hz to 20 kHz, providing the listener with both deep bass and a balanced midrange.