to avoid noise through the headphones; cuts out the sound when no audio signal is available
for the Sony MDR-IF330RK and MDR-IF230RK; works with your existing transmitter
so you can wear them comfortably for hours on end
with optional AA alkaline battery
with a separate self-adjusting band conforms precisely to the curve of your head; stays comfortable, even after listening for hours on end
in one earpiece conveniently adjusts the volume for both channels
lets you move around the room and still enjoy music or TV sound tracks; lets you turn the volume up late at night -- without disturbing anyone else
are larger than many portable headphones for deeper bass, lower distortion and wider dynamic range; frequency response extends down to a low 18 Hz
combine high energy and small size, for ample sound output
conserves battery life; the headphones turn on when you place them on your head
for the Sony MDR-IF330RK and MDR-IF230RK; enables two people to listen at the same time
lets you continue to hear ambient sound
ensure high rigidity for minimum distortion; low mass for extended high-frequency response out to 22,000 Hz
