KEF - Mu7

Bluetooth Headphones with ANC

KEF is a company renowned for producing high-quality audio equipment. Their esteemed speaker models, available in both passive and active versions and featuring Uni-Q drivers, are acclaimed not only in specialized audio press but also by audiophiles worldwide. KEF's entry into the mobile market has resulted in a range of diverse headphones, with the Mu7 model complementing their latest collection of mid-range wireless headphones. The Mu7 headphones are designed with users who value exceptional sound quality in mind.

DESIGN AND COMFORT

The KEF Mu7 stands out with its modern, minimalist design. Available in two colors (light gray and graphite), these headphones allow users to choose the version that best suits their style. However, their design may present some concerns:

Comfort:

The headband is well-padded, but the ear cups made of soft synthetic leather may cause excessive sweating of the ears. Furthermore, the clamping force of the headphones on the head is quite strong, which could lead to discomfort during extended listening sessions. Users may experience fatigue and pressure, especially during prolonged use.

Ventilation: The closed-back design means that the ears do not breathe, which exacerbates the feeling of discomfort and sweating.

SOUND QUALITY

The KEF Mu7 delivers impressive sound quality, though with some caveats. Here is a detailed breakdown of various aspects of the audio:

Bass:

The bass is deep and well-controlled, but it lacks extension in the lower range. Despite its detail, the sub-bass is not as pronounced, which may affect the enjoyment of certain music genres.

Midrange:

The midrange is clear, but the vocals are slightly subdued, which can make them lack fullness and clarity. Guitars also lack the necessary strength and weight, potentially impacting the overall dynamics of the tracks.

Highs:

The high frequencies are clean and precise, yet they can become strident during prolonged listening sessions. The headphones tend to emphasize high frequencies, which may lead to listener fatigue. These headphones can excel in high frequencies, provided they are paired with a source that does not further accentuate this range but rather slightly moderates it.

Soundstage:

The soundstage is wide and spacious, offering a sense of depth and accurate placement of sound sources. Instrument separation is excellent, allowing for easy differentiation of individual elements within a track.

Careful Source Selection

To maintain tonal balance and avoid harsh high frequencies, it is crucial to choose the right audio source. Sources with a warm sound and slightly subdued treble are ideal. Such sources help to balance the KEF Mu7's sound, ensuring that the high frequencies are neither harsh nor fatiguing.

Testing with various DACs has shown that the Mu7 headphones may overly favor the highest frequencies when paired with bright and detailed DACs. This results in a clean and clear sound, but with an emphasized treble that can become tiresome during extended and loud listening sessions. The KEF Mu7 performed better with a budget DAC like the iFi Uno, which offers a warmer sound, compared to the Chord Mojo 2, which rendered the high frequencies too piercing.

The KEF Mu7 excels with classical music, impressively reproducing piano and string instruments. The clear contours and outstanding instrument separation enhance the richness, three-dimensionality, and overall sound quality. In classical music, where detail and precision are highly valued, the KEF Mu7 meets these requirements exceptionally well.

ADDITIONAL FEATURES

The KEF Mu7 headphones are equipped with several features that enhance their functionality:

Active Noise Cancellation (ANC): The KEF Mu7 features an advanced active noise cancellation system that effectively eliminates ambient noise, allowing for complete focus on the music. However, engaging ANC with the snug, non-breathable ear cups can lead to overheating, sweating, and overall discomfort. The use of ANC can also exacerbate discomfort during louder or prolonged listening sessions.

Ambient Mode: This mode allows external sounds to pass through, which is useful in situations where awareness of the surrounding environment is necessary.

Built-in Microphone: The headphones come with an integrated microphone that supports phone calls and voice assistant functionality.

Touch Controls: The ear cups are equipped with touch-sensitive controls, allowing easy management of music playback, volume adjustment, and call handling.

Additional Accessories

Included with the headphones is a meticulously crafted case that provides protection and convenient storage. The case is robust, elegant, and perfectly fitted, further reflecting KEF’s attention to detail.

CONCLUSION

The KEF Mu7 headphones offer good sound quality, but their comfort leaves much to be desired. While the sound is rich and detailed, the high frequencies can become irritating during extended listening sessions. The closed-back design and substantial clamping force can lead to discomfort and ear sweating. To achieve the best sound quality and comfort, it is essential to carefully select an audio source, preferably one with a warmer sound profile. The KEF Mu7 can be a solid choice for audiophiles who prioritize sound quality and are willing to invest in a suitable audio source. Despite the comfort issues, within this price range, the KEF Mu7 can be considered a good option, delivering excellent sound attributes that will likely satisfy many audiophiles when paired with the right source.

TECHNICAL SPECIFICATION

Type: Over-ear, closed-back

Drivers: 40 mm dynamic

Additional Features: ANC (Active Noise Cancellation) / Ambient Mode

Frequency Response: 20 Hz – 20 kHz

Impedance: 32 Ω

Sensitivity: 108 dB SPL/V

Connectivity: Bluetooth 5.1, 3.5 mm audio cable

Bluetooth Frequency: 2.402 GHz – 2.48 GHz

Bluetooth Range: Up to 10 meters

Audio Codecs: aptX, aptX HD, AAC, SBC

Resolution: aptX 24 Bit / 48 kHz

Battery Life: Up to 40 hours (with Bluetooth)

Battery: Lithium-ion 1100 mAh

Included Accessories: Case, 3.5 mm jack cable, USB-C cable

Compatibility: Apple iOS / Android

Charging: USB-C

Weight: Approximately 330 g

Prepared by: Przemysław Łabędź