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Blue Microphones Mo-Fi Headphones review

Blue Microphones Mo-Fi headphones
Our Rating :
£484.39 from
Price when reviewed : £299

A wonderful sounding pair of headphones with an innovative built-in amplifier

Blue has a rich heritage in both consumer-friendly and professional microphones and audio tools, but the Mo-Fi is the brand’s first foray into headphones. While you might have expected the company to debut with a safe, middle-of-the-road pair, Blue Microphones has instead created somewhat of a surprise with the Mo-Fi by packing in an amplifier directly in the headphones.

The Mo-Fi looks nothing like other over-ear headphones geared towards the fashionably-inclined – the design is a strange combination of retro charm and futuristic lines and angles. The Blue Microphones branding on each ear cup has a quaint charm contrasted with the harsh angles, hinges and materials, which makes for a strange pairing. 

The hinged design itself is also a surprising design choice. While most headphones use a vertically sliding adjustment band, the Mo-Fi opts for a multi-jointed headband with a laptop-style hinge on each side to independently adjust the earcup positions to accommodate different sized heads. 

The peculiar headband adjustments don’t stop there, either. You are also able to adjust the tension of the headband itself by adjusting a dial-wheel that loosens or tightens the headband. A tight fit will seal out more external noise, while a looser fit will result in better comfort for extended listening periods. 

It’s a nice touch, as there’s nothing worse than a poorly fitting headband. It’s difficult for manufacturers to accommodate for everyone’s differently sized heads, so being able to adjust the tension is certainly useful. You’re able to rotate the wheel through three full revolutions, so there’s a lot of room for adjustment as well. However, all of these hinges and mechanisms mean the headphones are rather big and heavy at 466g. This is a weight you can definitely feel and there’s no chance of you forgetting you’re wearing the Mo-Fis.

Regardless of how many adjustments are available on the headband, they also couldn’t stop our ears rapidly overheating once encased by the soft-padded circum-aural earcups. While successfully sealing you away from external noise, they cause your ears to become very warm and sweaty as a side effect, becoming uncomfortable to wear for longer listening sessions. This is a real shame, as they sound fantastic.

The Mo-Fi’s main innovation is the inclusion of a powered amplifier built into the headphones themselves. Many high-end ‘audiophile’ headphones require a lot of power to drive them to a decent volume, making it difficult to use them with a portable music source like a smartphone unless you choose to carry around an unwieldy portable headphone amplifier.

That’s certainly not the case here. You’ll need to be careful to start playing music at a reasonably low-volume otherwise you risk doing your ears some damage. There are actually three settings for the amp: Off, On and On+. The latter setting engages the amp’s analogue low-frequency enhancement circuit to provide additional presence to the lower frequencies. The effect is incredibly subtle, however, so don’t expect Beats-level bass boost. 

With an impedance of 42 ohms, the Mo-Fis don’t actually require much to drive, so you’ll still get by with using your smartphone although you will need to turn the volume up substantially higher than when the amplifier is turned on.  It’s still a good option to have as a last resort but sound quality with the amplifier turned on is substantially improved. 

An amplifier is useful beyond just boosting the volume, however. The built-in amplifiers in most portable sources are usually lacking and will introduce distortion and sound degradation as they are pushed to their upper-limits. Using a quality headphone amplifier takes the load away from the music source and helps to keep them within their sweet-spot for sound quality. Smartphones and other portable devices also don’t have much room to dedicate to quality circuitry, so a high-performance amplifier is often given lower priority.

Sound quality was at times incredible. We heard fantastic detail from our test tracks and it was possible to pick out individual instruments easily with no hint of muddiness. Vocals in particular were crisp without any harshness. Bass was relatively reserved, even with the amplifier in On+ mode, but it was accurate and without distortion.

We could barely hear a difference between On and On+ on tracks that were mixed with a reasonable bass presence. The mode is more geared towards tracks where bass is lacking, as with some older recordings. Even then, it only brings subtle warmth to the low-end. 

Stereo separation was fantastic and the soundstage was surprisingly wide for a pair of closed-back headphones. Blue Microphones wants the Mo-Fi to appeal to audio professionals as well as consumers, so unsurprisingly the sound signature is very flat and accurate without any real colour. 

The internal amplifier needs charging, which is done using the Micro USB port located on the left earcup. We managed to get over 12 hours of listening at half-volume, which is a decent return. A small yellow light is built into each earcup that indicates when the headphones are turned on, as well as to show low battery level. This can actually be rather annoying at night, as the light is bright enough to be distracting. If you’re planning to wear these on a red eye flight, we can see the lights annoying other passengers. 

Blue Microphones Mo-Fi headphones

Happily, the headphones will automatically go into standby when you’re not wearing the headphones and the two earcups touch each other. This is handy as it’s easy to forget to turn a pair of headphones off resulting in a flat battery when you want to listen to some music. 

If the battery does die you are still able to use the headphones, albeit with the amp turned off in passive mode. This is in stark contrast to headphones like the Beats By Dr. Dre Studio that will cease to work as soon as the battery dies due to the dependence on the built-in digital signal processor (DSP) for audio processing.

In terms of accessories, you get both a 1.2m cable with integrated volume controls and microphone, and a 3m audio cable, which will be useful if you want to use the headphones connected to a home hi-fi system. Blue Microphones even provide a 3.5mm to 1/4in adaptor. If you’re connecting the headphones to a source with a quality amplifier already, it’s a good idea to turn off the headphone’s amplifier as it won’t be needed. 

As Blue Microphones’ debut pair of cans, the Mo-Fi sounds fantastic and the built-in amplifier really makes your music shine. They will, however, bring out the distortion in any low-quality encoded tracks you might have in your collection. They sound far superior to the Beats By Dr. Dre Studio headphones, which are available for the same price.

However, the design is divisive and they’re slightly let down by their lack of comfort. If comfort is important to you, consider the Sennheiser Momentum headphones which are supremely comfortable and look great, but don’t sound nearly as good.

Buy Now: Blue Microphones Mo-Fi

Headphones subtypeOn-ear headphones
Headphones driverClosed
Active noise-cancellingNo
Power sourceLithium-Ion battery
Headphones sensitivity105dB
Frequency response10-20,000Hz
Headphones impedence42 ohms
Plug type3.5mm headset jack plug, 3.5mm audio jack plug
Inline volumeYes
Cable length1.2m, 3m
AccessoriesCarry case, USB charging cable, airplane adaptor, 1/4in adaptor
Buying information
WarrantyOne-year RTB
Part codeMo-Fi

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