The Sennheiser headphones are now available in India for the true audio lovers. Being one of the leaders among all the players in the noise cancellation game, Sennheiser's new offering, the PXC 350, is surely as good and worthwhile as the rest. It has slots for battery insertion on both the left and right ear cups. The active NoiseGard circuit on the left cup gets activated by an on/off slider switch placed on the bottom. When slid on, a small red LED is exposed. NoiseGard is a proprietary name given to the same technology that all these headphones use. Basically, sound up to 1 kHz is filtered out by an out-of-phase wave generated by the circuit. The reference for this wave is the background noise around your ears, which is picked up by mics in the circuit. The rated frequency response is quite vast at 8-28,000 Hz, though 108 dB SPL for the sound power is acceptable. Here are some merits and demerits of the headphones:
•Great passive noise cancellation
•Clear sound, even at full volume
•Impressive build quality Demerits:
•Noise induced by active circuit
•Price on the higher side (Rs.19, 900/ - )

The passive noise cancellation is quite phenomenal;with at least 30dB of background noise being reduced, leaving just low hums and vocal murmurs. The bass was nice and round, and in perfect tandem with the timing part of things. Mids and highs too were very sweet-sounding. However, the highest volume is not as loud as in some other models. Also, the noise reduction circuit does not filter noise completely; the amp hiss and a high-frequency hum are clearly audible. To sum it up, this headphone has a praiseworthy look, design, built, and sound. However, the sound production is better in passive mode than in active mode. Although, the low hum of background noise is completely erased in active mode, the inherent noise of the system persists.' The price, set at Rs 19,900/- is indeed on the higher side.