KEF Mu3 review

KEF aims to take a slice of the true wireless earbuds pie Tested at £199 / $230 / AU$300

KEF Mu3 review
(Image: © KEF)

What Hi-Fi? Verdict

KEF’s first noise-cancelling wireless earbuds make a positive impression, even if they fall short of being best-in-class


  • +

    Refined, mature balance

  • +

    Weighty bass

  • +

    Good battery life


  • -

    Beaten for dynamics and expression

  • -

    Call quality could be better

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KEF has dabbled in the headphone market since 2013, experimenting with both over-ear and in-ear models over the years, however it’s fair to say the hi-fi giant hasn’t set the headphone market alight. But could all that be about to change with the ambitious Mu3?

The Mu3 are KEF’s first-ever wireless noise-cancelling earbuds and, in terms of price, slot somewhere in between the big-hitting Sony WF-1000XM3 and the Bose QuietComfort Earbuds.


KEF Mu3 build

(Image credit: KEF)

If you haven’t heard of Ross Lovegrove before you buy the KEFs, you will have by the time you have unboxed them. His name is emblazoned on the packaging, the instructions and even on the inside of the Mu3 case.

Lovegrove has helped design several KEF products in the past, most notably the KEF Muon – an impressive-looking pair of limited-edition, aluminium, floorstanding speakers that cost an impressive £140,000 ($198,000) per pair. He also played a major part in designing the Award-winning KEF Muo wireless speaker, and now he has turned his hand to a pair of true wireless earbuds.

KEF Mu3 tech specs


(Image credit: KEF)

Type True wireless in-ears

Bluetooth Yes

Noise-cancelling Yes

Battery life 9 hours (+15 hours from case)

Weight 5.8g (each)

From the moment you take the headphones from their packaging, you can see Lovegrove’s involvement. The case looks like a large blob of liquid metal but has a nice subtle shape. It feels robust, too, while the smooth glossy plastic helps to give a more premium first impression. It’s a similar story when you open the case up. The Lovegrove name on the inside might be one nod to the designer too many, but the sheen from the small silver earbuds also gets your attention.

The buds look and feel in keeping with the case, from the smooth glossy exteriors to the KEF logo imprinted on the surface of each bud. They’re surprisingly small, which makes them a little slippery when placed between finger and thumb, but getting them in place with a good seal isn’t too tricky. Pick your eartips (there are four different sizes to choose from), drop them in and twist the buds slightly to lock them into place.


KEF Mu3 comfort

(Image credit: KEF)

Provided you achieve a good seal, the level of passive noise isolation on offer is decent. While finding them pretty comfortable for a brief stroll, we are a little less convinced of their comfort during longer listening sessions. The Sony WF-1000XM3 are a slightly bulkier design but feel much less intrusive, as do the Bose QuietComfort Earbuds.

The first time you open the case, the headphones automatically start the pairing process. Once partnered to your headphones, they connect almost as soon as the lid is lifted.

On the outer surface of each earbud, you’ll find a small KEF logo that sits on a circular control button. There are no touch controls here, but the physical ones work perfectly well – and also means you won’t accidentally hit play or skip a track when putting them in place.

On the left earbud, a long press turns the volume down, while a short press switches the noise-cancelling on or off and engages the ambient mode (which lets you hear your surroundings without having to take the buds out of your ears). On the right earbud, a short press answers calls and plays or pauses music and a long press increases volume. Pressing twice stops your phone call or skips forward a track.

Battery life comes in at an excellent nine hours, with the case giving a claimed extra 15 hours of additional juice to keep the buds going. By comparison, the class-leading Sony WF-1000XM3 offer around six hours. If you’re caught short, a quick five-minute blast from the charging case (which uses USB-C) should give you an hour of playtime.

There’s a small LED on the case which blinks when the battery is low, but it’s not that obvious against the glossy plastics and it also doesn’t give any real indication of just how much charge is left. We were caught out when our buds needed charging, only to find the case was also running on empty.

Unlike many wireless earbuds around this price, there’s no app to accompany the KEF Mu3. This means there’s no EQ adjustment for you to play with, but that’s only an issue if you aren't happy with the balance of the KEFs. And we can't see why you wouldn't be.


KEF Mu3 sound

(Image credit: KEF)

The KEFs produce a wonderfully balanced sound that’s smooth and refined. They’re quite effortless in their delivery and present the music in a mature and sophisticated fashion, making them easy to listen to over prolonged periods. You can push them to the limits of their battery life and emerge on the other side not feeling drained or tired of their sound.

We play Shout by Tears For Fears and notice fullness and finesse to the percussion, plus a good amount of space around the instruments. There is no hint of harshness as chimes cut through the song’s rich vocal and solid, yet relatively mild-mannered bass. However, the Sony WF-1000XM3 deliver the song with a greater sense of sparkle, proving capable of finding an extra gear when it comes to drama and drive.

Switch to Hayden Thorpe’s Diviner and the smooth, soulful delivery of the track plays to the KEF’s strengths. His vocal is rich and full-bodied with a good sense of expression, while the individual strokes of the piano keys come across well. Again, the Sonys take this level of dynamics and expression up a notch, forming a tighter emotional bond with the listener.

Moving on to Massive Attack’s Angel, the KEFs cope well with the track’s powerful and relentless bassline. There’s a richness to each bass pulse and they sound solid, even if rivals can paint them with greater texture.

The Mu3 do a good job of keeping outside interference to a minimum. Their noise-cancelling tech doesn’t produce such stark results as the Bose QuietComfort Earbuds, but it’s effective and, anyway, not everyone is comfortable with the vacuum-like feeling that more aggressive noise-cancelling technology can have.

The call quality could be better, though. While the best pairs of true wireless earbuds lend your voice a more natural-sounding quality, the KEFs have a slightly coarse edge and introduce more compression.


KEF has put its head above the parapet and produced a pair of true wireless earbuds that can be considered worthy rivals to the Apple AirPods Pro. However, we have some reservations about the call quality, and while nothing about the performance stands out as being a negative, the Mu3 can’t quite match the sonic ability of the class-leading rivals at this level from the likes of Bose and Sony.

However, if you’re a fan of the KEF brand – or Ross Lovegrove in particular – and have the funds at your disposal, it’s well worth giving them a chance.


  • Sound 4
  • Comfort 4
  • Build 5


Read our guide to the best wireless earbuds

Read our Sony WF-1000XM3 review

Read our Apple AirPods Pro review

Read our Bose QuietComfort Earbuds review

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  • bristollinnet
    Another 'lifestyle' product with average sound from an audiophile perspective. KEF (like B&W before them) are moving further away from their core expertise, and it shows.
  • N1ck
    Have you heard them? Which alternatives would you recommend that offer audiophile grade music at that cost level?