The M500 headphones have a strikingly simple and modern design – a sleek combination of black vinyl and matt silver aluminium which looks right at home with a MacBook or iPad. See also Group test: What are the best headphones?
They come with a hard carry case and their 'smart hinge' folding design lets the earpieces swivel 90 degrees to make them more suitable for travelling.
We did find the M500 headphones difficult to get adjusted to in terms of ergonomics. They were quite awkward to get seated comfortably on our head, in part due to their rigid structure. It also doesn't help that the size adjustment mechanism is very stiff, so you have to take them off, make a change, then see if you've got it right.
After a while, however, once we'd cracked the puzzle, these headphones were extremely comfortable. The super-soft memory foam cushions feel luxurious on your ears and the stiff arms mean no more adjusting once you've got them set correctly.
Sound isolation is acceptable with a closed-back design but these on-ears aren't as good as you'd find from over-ear alternatives.
Aside from the regular flat 1.3 m cable, there's a second cable included with in-line controls and a microphone for use with Apple products; the pause/play button worked with an Android smartphone too. KEF also includes a flight adaptor and a 6.3 mm (1/4in) jack adaptor.
KEF M500 review: Sound quality
They took some running in to help overcome some midband reticence but we then felt we were in the same room as the band.
The headphones have a nicely even frequency response with bass that wasn't over the top in level, and a high-frequency response that was far from piercing. It gave all the frequencies a chance to shine and present a clean and precise soundscape.
A downside to their ecumenical manner was that they could sound rather flat at times, lacking somewhat in dynamics and colour.
Overall we liked the crisp and clear sound produced by the M500 'phones. It's a commendable effort even if it's not quite the ‘awe-inspiring speaker quality reproduction from headphones' which KEF promised.