KEF Mu7 Review
KEF's Mu7 headphones have been extremely popular since their launch late last year - one of the highest selling headphones we've seen in recent times.
We thought we'd spend one week with the Mu7 as our daily headphones to see how they would stack up with daily usage.
Unboxing
The Mu7 come packaged in with a slim travel case, USB charge cable and 3.5mm cable.
Within the travel case is an accessory compartment for storage of the above cables. In a beautiful piece of industrial design, there is an elegant magnetic cover to keep the cables safe and secure when on the move.
The headphones come pre-charged and were able to used straightaway. Pairing was effortless - simply turn on the Mu7 and the headphones start up in in Pairing mode. A few quick taps on the iPhone to access Bluetooth settings and within seconds the Mu7s were paired and ready to go.
Comfort and Build Quality
One of the standout features of the Mu7 is the build quality. Just picking them up and placing them on your head is enough to know that these are a premium product - the feel of the high quality materials, the silicon in the headband, to the feel of the earcups - all these things scream quality. They're extremely comfortable as well - even having them on all day, we barely noticed they were on. The clamping force is well balanced as well - firm but not uncomfortable, and never once did they feel like they would fall off.
Sound
Day by day, we found the sound changed for the better. The first day, we found that the sound was a little restrictive - sounded like the drivers were all really tight. Volume level was good, even better than the Bose QC35s that we have lying around. Midrange response was very strong, although the bass sounded a bit lacking and the top end was on the bright side.
We left these playing overnight, and 24 hours later we noticed that the bass was markedly improved with much greater extension. The soundstage was very wide - almost sounding like a pair of open back headphones.
By the fourth day of burn in, the Mu7s were sounding amazing. Full soundstage, very open, great depth and detail, strong bass response and accurate placement of instruments and vocals. These really are an amazing sounding set of headphones.
Phone Calls
A big part of Bluetooth headphones is their function set - lots of people would use these in the office, and so they had to function well as a Bluetooth headset as well. Good news is that call quality is excellent, both receiving and speaking. There weren't any annoying echoes or delays, and again, compared to the Bose QC35s, the Mu7s were a clear winner. KEF use a technology called CVC (Clear Voice Capture) that detects voice and separates it from background noise - it is extremely clever, and in practical situations it works really well.
Noise Cancelling
The KEF Mu7s come with 3 selectable modes: "ANC On", where ANC is on full blast, "Smart ANC", where the Mu7s let some speech through and remove the background noise, and "Off", where noise cancelling is turned off entirely.
To test the noise cancelling, we put them on and stepped out onto the busy Parramatta Road. With ANC On, it blocked out almost all the road noise, leaving only the music. Smart ANC worked as expected - with someone talking near you, around 1-2 metres, the voice comes through and its easy enough to understand them. Another win!
Charging
Included in the case is a USB A to USB C charging cable. Using a 5V 1A Power supply the KEF Mu7s were fully charged in about 4 hours, and lasted about 40 hours with ANC On before requiring another charge. We didn't test this second part, but KEF say that with a 15 minute charge, the headphones will last for 8 hours. That's very impressive and up there with the best headphones on the market - if your headphones are flat while changing flights, a quick 15 minute boost will make sure your headphones are ready for the next leg.
Overall
The sound is perfect for casual music listening. Just like KEF loudspeakers, they aren't fatiguing and its a very enjoyable experience. Some might find the clamping force a little strong, but over time the headphones will shape and soften to the width of your head. If you do find them too strong from the get go, try clamping them over some books for a few days and the headphones will expand. Overall, these are a winner, and we can see why they have been as popular as they are!