The MH40 are premium over-ear, closed-back headphones with a striking retro design and sumptuous build quality.
If the overly hipster-ish looks of these brown leather ones aren't to your taste, there are six other colour combos, including a stealth option with black leather and blackened metal.
Master & Dynamic MH40 – Design
These truly are beautifully crafted headphones. The combination of matte and polished metal, the neat stitching on the leather, the photo-etched logos – it's all impeccable. Even the detachable cables – there's a choice of with or without a three-button inline remote and mic – are silver-coloured braid with gorgeous etched and knurled plugs.
Unusually, the MH40 have a 3.5mm jack socket on each earcup, so you can choose which side you want the cable attached. It's a very neat touch, and another is a small mute button on the right earcup which can be pressed to instantly silence the headphones.
The earpads are a little bigger than those on the Sennheiser Momentum, meaning they didn't feel such a squish as the Sennies, and the ability to twist the earcups meant they positioned on my head better.
However, the MH40 are monstrously heavy at 360g, and still not as comfortable as many other over-ear models, especially on long listening sessions.
Despite the mesh backs of the MH40, which are just for show, these are closed-back headphones, so the earcup behind the 45mm Neodymium drivers is sealed. The disadvantage of this design is that it doesn't deliver the wider, airy sound of open-back headphones, and makes the music more boxed in around your ears. On the upside, closed-back headphones are far better for public places instead of just home listening.
In spite of their closed design, the MH40s manage to give a glimpse at what truly high-end open-back headphones can really do. Soundstaging that makes the music feel like it's coming from further away than just your outer ear, wonderful timing, bass that gets you right in the gut... But they just fall a little short of offering the complete sonic package.
The mid-range is a tad congested, with vocals feeling oddly closed in, and really fine acoustic detail getting a bit lost. The Sennheiser Momentum do a much better job in this respect, even if they have nowhere near the breadth of soundstage. AKG's open-backed Q701 offer a better overall sonic balance.
The bottom end, while undoubtedly tight and thunderous, can also be overpowering and offputting. The bass drums in Beirut's “Postcards From Italy”, for instance, are so prominent as to become distracting.
If you value a huge, warm sound over subtlety, the Master & Dynamic MH40 are well worth a listen. They're so eye-catching that you could even just leave them on the coffee table as a talking point.
However, I did find they weren't quite the best at controlling sound leakage, so the Sennheiser Momentum and OPPO PM-3 are worth considering as better travel companions.
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Fun headphones with powerful bass and a wide soundstage, but they lack subtlety.