Noise cancelling headphones: what the marketing leaves out

Active noise cancellation works best on low, steady frequencies: aircraft cabins, train carriages, air conditioning. It works far less well on speech, which is exactly what most office workers want removed.

If your problem is colleagues talking, passive isolation from the earcup seal matters more than the ANC processing, which pushes you towards over-ear designs with deeper pads.

Watch for multipoint pairing if you switch between a laptop and a phone. Its absence is a daily annoyance that no amount of sound quality compensates for.

Battery figures are usually quoted with ANC on but at moderate volume. Expect to lose roughly a fifth of the quoted runtime in normal use.