German audio company Sennheiser has expanded its premium PXC series. The company has launched PXC 550 wireless headphones priced at Rs 29,990. Targeted at business travellers, the device onSennheiser’s India e-store.Sennheiser PXC 550 Wireless headphones come with Bluetooth and NFC support and promise to deliver 30 hours of battery backup. The headphones features a touch sensitive trackpad integrated into the earcups. The trackpad enables users to control their music and volume levels on the go. The headphones also have a built-in timer to avoid sudden and extreme sound levels.The company claims that the device is compatible with its music players and sound tuning app CapTune. The app offers adjustments with the equaliser and also features sound check. The headphones come bundled with with an inline remote control, carry case, USB cable and quick setup and safety guide.Recently, Sennheiser launched its HD400 series over-ear headphones. The series includes three headphones — the HD 451, HD 461 and HD 471.All these headphones are compatible with Android and iOS devices. While the company’s (i) version are compatible with iOS models, the (G) versions sync with Android-only.The company claims to have used native neodymium magnets inside the headphones. According to Sennheiser , while HD 451 and HD 461 models throw powerful bass, the HD 471 is more balanced in terms of bass and treble.