In this age of blink-and-you’ll-miss-them tech product cycles, we should be tipping our hats to Sennheiser’s HD 650 headphones, which have been knocking around since 2006 and are only now getting a long-awaited successor. Design-wise, the HD 660 S’ (£429.99) have a lot in common with the previous model, keeping the open-back form and cups the size of small frying pans. The new matte black finish is a nice touch. Break them open, though (don’t actually do this), and you’ll find Sennheiser’s proprietary transducer, which it says delivers lower harmonic distortion for more natural audio. And because impedance is at a lower 150 ohms, you should be able to use them with mobile devices as well as high-end, stationary HiFi systems. This makes them more versatile than the previous model, and future-proofed for another decade of service to audiophiles.