Sennheiser is adding to its popular range of noise-cancelling headphones with the arrival of the rather upmarket PXC 450, which uses technology originally designed for commercial airline pilots. Both BA and Lufthansa use flight-deck headphones with the company's NoiseGard 2.0 technology, which claims to remove 90% of all bass rumble and noise, such as that from engines, tyres etc. The new £300 headphones also feature Active TalkThrough, which allows the user to have a conversation without removing the headphones at the push of a button, while still maintaining noise reduction. That'll be handy for those 'could I have another glass of water?' moments, then. In addition, the over-ear design with soft earpads keeps out more extraneous noise, there's a built-in electronic volume control and the headphones are designed for 20 hours' operation from a single AAA-type alkaline battery. However, they'll still work as conventional headphones if the battery is drained, which should cover the last few hours of that London-Sydney flight. You can also remove the cable and simply use the NoiseGard 2.0 system while you sleep, and the headphones fold up for easy packing.