Sennheiser’s active noise-cancelling PXC 350s fit snugly around the ear. This helps reduce background noise, even without the noise-cancelling circuit engaged. Turn it on, however, and the din of air conditioning and engine noise retreats into the distance, replaced only by a slight hiss. Sound quality is crisp, with a deep, tuneful lower end and, despite questionable looks, the PXC 350s are more comfortable than physical noise-isolating earphones. The unwieldy battery pack of cheaper models has also gone – pop an AAA battery in each earpiece and the volume control dangles from your neck. Thankfully, they also work well passively. They’re good value too.