The extremely popular K 270 Studio have unfailingly proven to be a reliable tool over the years. The new K 271 Studio, while providing the same performance as the K 270 Studio, is much lighter and easier to use, and still provides a natural, pristine sound. The closed-back, circumaural earphones provide maximum attenuation of high ambient noise. The K 271 Studio are also ideal for all applications where no sound must leak from the headphones. The headphones switch off automatically when taken off. Since this feature prevents headphone signals from spilling over into an open microphone it is highly appreciated by recording studio, live sound, TV sound, and broadcast engineers. Features For onstage and studio use Circumaural earphones High noise attenuation Automute feature mutes headphones when they are taken off Specifications Type: closed-back, circumaural dynamic headphones Sensitivity: 91 dB SPL/mW Frequency range: 16 to 28,000 Hz Rated impedance: 55 ohms THD: 0.3 % Cable: plug-in, 99.99% OFC single cable, approx. 3 m (10 ft.) Connector: gold plated stereo mini jack Adapter: gold plated mini to 1/4" screw-on adapter jack Net weight: (without cable) 240 g (8.5 oz) Special features: plug-in cable with mini XLR connector