Audiofly AF140 MK2 Hybrid In-ear Monitors Review

Posted on 3rd October, 2019

Audiofly AF140 MK2 Hybrid In-ear Monitors Review

Based in Perth, Audiofly designs and develops some of the only Australian-based IEMs on the market. We got our hands on a pair of Audiofly's latest AF140 MK2 IEMs for review.


AF140 MK2

Professional Hybrid In-Ear Monitors

$399.99 RRP

Working in the professional live audio industry, I am often asked for my recommendations on In-Ear Monitors (IEMs).

The answers are often similar; for custom IEMs, grab yourself a set of JH Audio IEMs. For universals, try Shure or Sennheiser. These are all great offshore options, but what about something locally designed and produced instead?

Audiofly has been around since 2012. Based in Perth, they design and develop some of the only Australian-based IEMs on the market. The website describes the Audiofly team as “a fierce, rag-tag group of creative individuals, including musicians and music lovers, pop-culture nerds, coffee enthusiasts, foodies and beach freaks based out of Perth, enjoying the Summer vibes.” 

Audiofly has a substantial “something for everyone” approach to the IEM market. On the cheaper side of things, the AF33C MK2 is a single dynamic driver IEM which will cost you less than $40 brand new. On the premium end of the scale, the AF1120 is a six-driver, 3-way stage monitoring beast, coming in at a cool $849.99. 

I managed to get my hands on a pair of Audiofly's latest AF140 MK2 IEMs. This 3-way hybrid stage monitor comes in at $399.99 RRP, challenging the Shure SE425 ($378), Sennheiser's IE 80 S ($399) and the Westone UM Pro 20 ($399).

I was curious how our homegrown, true-blue little fella would stack up.

in the box

Included in the box:

  • Two sets of Comply “T” series tips
  • Three sets of triple flange tips
  • Three sets of standard olive tips
  • One set of foam tips
  • An airline adapter
  • A 3.5mm to full-size adapter (gold plated)
  • A cable velcro tie
  • A soft textured hard case


Audiofly's AF140 MK2 are marketed towards the pro-audio market, which is apparent the minute you open the box; the included hard case is rugged enough to toss into a toolbox or backpack after a long gig.

The removable 1.2m Audioflex SL twisted cable is reinforced with CORDURA Fibre (which is often used in military wear). The benefit is a cable which frankly feels like it could survive getting run over by a forklift.

The connections on either end of the AF140 MK2's cable are crucially important. On Mk1 of these IEMs, Audiofly had modified the standard MMCX connection by notching the housing around the connector, which limited the excessive swivel and rotation. Based on feedback from its customers, Mk2 has returned to a standard MMCX connector allowing owners the choice of cables. The other end sports a sturdy right-angled plug.

The quality and reliability of the cables cannot be understated. It might sound like I'm banging on about the cable too much, but in the live performance world, IEM cables can either be your best friend or your worst enemy. They get rolled up in an instant, thrown in and out of bags, and if I'm honest, poorly handled. When worn, cables will often get snagged on mic stands, audio console covers, door handles, and anything else within reach. Having a bulletproof cable like the one found on the AF140 MK2 is a lifesaver when you're on the road.

The plastic housing of the IEM is finished in gunmetal colour with a magnificent metallic finish and is very lightweight. With hooks built into the cable just above the housing, these can only be worn over the ear.

Inside the headphone

Traditionally, higher tier IEMs will come in either one of two flavours: either a single dynamic driver handling the output of the entire audible frequency spectrum, or several smaller balanced armature drivers doing the legwork with a specific frequency range being dedicated to each.

There are advantages and disadvantages to each type. Some will tell you that a single dynamic driver will have much more presence and punch in the low end due to much more surface area being pushed. The downside is that with only one driver doing all the work, the details won't be perfect in the rest of the spectrum.

People will also say that multiple balanced armature drivers will have plenty of razor-sharp precision, but lack “oomph” in the bass, and that tuning a teeny tiny crossover to perfection is a much harder task than many realise.

The AF140 Mk2 is a “hybrid” design, featuring a single 9mm mylar Neodymium dynamic driver for the low end, and single balanced armature drivers for the mid and high frequencies, all tied together with a 3-way crossover which contains a Butterworth filter. 

After being processed by the 3-way crossover, the acoustic funnelling and tuning is routed through a physical 2-way frequency divider before it hits the ear.

Using the headphone

The AF140 MK2 is a simple over-ear affair, with integrated ear hooks built into the cable. Considering the slim and lightweight body of the IEMs, I had no issues with fitting them in quickly or getting a solid seal. The enormous amounts of supplied tips certainly helps here too.

With the impedance hovering around the 17ohms mark, you'll want to be a little bit careful of the damping factor when selecting which source to pair these IEMs with. If you're aiming for a ratio of around 1:8, you will want to pair these with a source that has less than 2ohms of output impedance, or you may fall victim to a wonky frequency response or distortion.

Thankfully in 2019, devices with an output impedance of 2ohms or less are very easy to come by.

Fortunately, the cable doesn't physically “remember” how you bent, cramped or squished it into its carrying pouch, and always comes out of storage with a very forgiving straight line each time.


Once I established a good fit and seal, I relaxed back into my chair and hit play on Camberwell by FloFilz. One thing this song highlighted straight off the bat was the deep and pronounced bass presence of the 9mm dynamic driver. The bass comes through with a guttural rumble but retains its tonality accuracy and is layered nicely. The gentle saxophone notes linger gently through the mid and upper midrange and come through with excellent clarity, delivering a powerful bassline at around the 1:05 mark. 

Stepping up the pace with a rousing rendition of Cold Harbour by Dark Sky, this energetic dance music tune is an excellent test for dynamic driver IEMs. It has plenty of midbass thumps, but also high paced midrange splashes, such as the bongo drums that rapidly beat at around the 1:30 mark. The bass certainly takes centre stage once again, but the 9mm driver can keep up with the demanding pace of the track in the midrange as well. When the high hats kick in at the 2:00 minute mark, it was smooth and subtle, not shrill or offensive at all.

An excellent test of a headphone's dynamic range is Clubbed to Death 2 by Rob Dougan. Not to be confused with the similarly titled track (from the same artist) that was made famous by the movie “The Matrix”, this tune features a familiar-sounding hailstorm of drums, with gentle string samples floating throughout. It's a formidable test for the AF140 MK2, but one that the IEM takes in its stride. The unrelenting bassline is overwhelming yet doesn't cause any mishaps in the midrange, and the piano samples show off the accurate tonality of the midrange. For home listening, I found myself wishing for the lower midrange to be more pronounced for some of the gentler sections, but when the bass kicks back in I forget about it entirely and started toe-tapping instead. 

The AF140 MK2 has a slightly darker sound signature with plenty of midbass ability and wallop, which is perfect for stage and professional use in a live environment. They also respond incredibly well to EQ in any frequency region, which would be perfect for tuning these puppies to an artist's or engineer's tastes. If you want to suck out some of the delicious bass and tune in a little more midrange, the AF140 MK2 doesn't bat an eyelid when doing so.


For an In-Ear Monitor that is marketed towards professional and stage use, the AF 140MK2 well and truly ticks this box. They will also please those wanting a quality pair of IEMs for street use with their bass and midbass response.

The slightly darker sound signature, complete lack of sibilance, as well as an excellent ability to respond to EQ pushes the AF140 MK2 almost beyond their reasonable asking price.

With a robust and reliable cable and connectors, Audiofly's latest offering can proudly stand on its own two feet against its international competitors.


  • Driver type: 9mm single mylar/neodymium dynamic and dual balanced armature drivers
  • Driver arrangement: single dynamic bass driver, single balanced armature mid, single balanced armature high
  • Frequency range: 15-25kHz
  • Crossover: Passive 3-way electronic crossover with Butterworth filter
  • Acoustic tuning: Physical 2-way frequency divider
  • Impedance: 17Ω
  • Sensitivity: 100dB at 1kHz
  • Cable length: 1.2m / 47”
  • Plug type: 3.5mm gold plated, right angle format

For more information visit Audiofly.


    Matthew Jens's avatar

    Matthew Jens

    Constantly keeping himself busy, Matthew is a production manager, Brazilian jiu-jitsu blue belt, Head-Fi fanatic, coffee enthusiast and all-round cool Dad.

    Posted in: Headphones
    Tags: audiofly 

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