Sennheiser Electronic Corp.","The PXC 450 is a circumaural high-end travel headphone set with NoiseGard™ 2.0 technology and TalkThrough function for the best possible attenuation of ambient noise.The PXC 450 enables an unprecedented sound experience for people on the move, thanks to its adaptive baffle damping in combination with the patented Duofol diaphragms, which prevent unwanted partial oscillation and thus guarantee a highly natural, lifelike sound quality.NoiseGard™ is an active noise compensation system which Sennheiser originally developed for use by pilots, who have to rely on good sound quality and efficient protection against ambient noise even in high-noise environments. NoiseGard™ actively compensates the noise, based on the physics principle of sound and counter-sound, which works as follows: tiny microphones pick up the low-frequency ambient noise in the vicinity of the user's ear. Based on that noise interference, the NoiseGard™ electronic module calculates the required counter-sound wave with 180° phase inversion. The unwanted noise and the phase-inversed wave meet directly at the user's ear where they virtually cancel each other out. The result is an effective reduction in ambient noise. The music is transmitted in the same high quality, so that even quiet passages can be enjoyed in noisy environments.NoiseGard™ 2.0 has perfected the NoiseGard™ principle thanks to the use of optimised circuitry design and even more efficient processors. It also uses better quality microphones, which enable more sophisticated pick-up of unwanted noise. Specially developed filter algorithms enable improved active noise compensation of up to 90% (23 dB). It is of course also possible to use these headphones passively, i.e. without NoiseGard™ and without batteries.Users of a PXC 450 who wish to communicate with their neighbours can do so without taking off the headphones: when the TalkThrough function is activated, professional quality microphones mounted on the outside of the headphones pick up all acoustic signals in the immediate vicinity. Unwanted background noise, such as the sound of the engines on a plane, is filtered out electronically to a great extent, so that only the neighbour's voice is passed on through the headphones into the user's ear in top audio quality.
