There's a lot that can go wrong with noise-cancelling wireless headphones compared with a regular pair of wired headphones.
Finally there's the risk that all the effort and space dedicated to delivering decent battery life and wireless connectivity means there's little budget or materials left to offer a pair of headphones that actually sound great to listen to.
They're not hampered by poor battery life or connectivity, and they don't sound half bad, even when connected over standard Bluetooth rather than the enhanced Bluetooth aptX.
The Sennheiser PXC 550 headphones aren't bad looking per se, but they're certainly very conservative in appearance.
The two earcups are made of matte plastic, with a simple oval metal band on each which houses the microphones the headphones use for noise cancellation.
A single button deals with both switching between the headphone's four equalizer modes and bluetooth pairing duties, while a slider enables you to choose between two different kinds of noise cancellation, or turn noise cancellation off entirely.