Arguably the most popular headphone made by the Japanese AudioTechnica is the venerable ATH-M50x. It has long been the go-to recommendation for both listeners and sound creatives as well. This time we’re looking at its younger brother, the ATH-M40x to see whether it shares the same pedigree and does it hold some aces up its sleeve the older M50x doesn’t.

Pros
  • A feature-rich package
  • Replaceable cable
Cons
  • Not really tonally neutral
  • High-ish THD with odd harmonics dominating the lows
  • Comfort isn’t great
Use cases Best use case:
Mixing and tracking should be doable with these, for mastering something with a cleaner THD profile will be more suitable
Tech specs Type
Closed back, Over-ear
Impedance
35 Ohm
Distortion
<2%
Frequency response
15 Hz to 24 kHz
Connector
3.5 mm stereo jack
Adapter
Screw-on 3.5 to 6.3mm adapter included
Weight
240 g (without cable)
Require headphone amp
No
Headphone amp

The M40x with its 35Ohm impedance and generous sensitivity can be easily driven from any headphone output out there. Even low-powered options like laptops, tablets and cell phones should be able to provide enough volume and headroom to work with high dynamics material. The lowish 35Ohm impedance can be a nuisance when dealing with older devices which can have high output impedance which will shift the tonal balance of the headphone, as a tonal shift will be incurred.

Build quality

While the ATH-M40x looks rather similar to the M50x, the plastic used in its construction seem to be of lower quality. The headphone also uses hinged yokes to fold up neatly for transportation, which add extra modes of failure. Earpads are made out of artificial leather and are replaceable without much effort. The rest of the earcup can be taken apart with a small screw-driver, should a driver fail and call for a replacement. A welcome feature is the replaceable cable which should add considerably to the ATH-M40x’s longevity.

Sound

Sometimes this tonal response is called the W-curve, so generally one can think of it as a U-curve with colored mids. Generally the scoop between 100 and 1000Hz isn’t very audible, as it’s gentle, but it will change the sound of just about every instrument or sample with mid-band content. The other scoop at upper mids is something that’s present in many headphones and again isn’t annoying, but takes away the crunch of distorted guitars and synth lines. The boosted treble will impart the sound with fake detail and will emphasize overtones on just about every instrument. Together with the 3kHz scoop it will make getting snares to translate right a challenge.

Channel balance

Audio-Technica has done a really good job here! The channel matching on the ATH-M40x outdoes the ATH-M50x, as it doesn’t have imbalance in lower mids and bass. The highs do show some discrepancies, but they’re hardly audible and won’t mess with the imaging in an audible way.

Comfort

Comfort on the ATH-M40x isn’t stellar, the headphone clamps rather hard and the earpads aren’t too soft either. The headband padding also seems too hard and will exert pressure on the top of your head. Overall they wear okay, but these shortcomings become a nuisance after a few hours. The pleather on the pads is also on the cheap side and will make your ears sweat.

Value

As a package with two cables and a carrying pouch, the ATH-M40x is a decent offering for the price. It’s not a low-price closed-back class leader, but one can do a lot worse for the money. If you keep the frequency graph handy and remember the limitations of this headphone, it will help in crafting nice mixes.

Observations on how headphones perform after applying Sonarworks Reference correction Total Harmonic Distortion

The distortion profile shows 3 distinct problems – the small peak at upper mids, the mid peak and high odd order distortion in the bass. All of these can’t be calibrated away and suggest that resonances can be present at these frequencies.

How accurate and consistent is the correction effect among different listeners?

There’s little room for your ears to wiggle due to medium sized earpads, so consistency generally isn’t bad. The ATH-M40x also works better with average calibration profiles due to absence of channel imbalance.

How much do they differ pair to pair in terms of frequency response?

Overall not bad for an entry level headphone, HyperX Cloud 2 is better at this.

Rating

Build 6
Sound 5
Comfort 5
Harmonic Distortion 5
Channel balance
8 /7
Accuracy and consistency
7 /7
Value 7
Out of the box
With Sonarworks Reference correction

Conclusion

Calibration sets the tonality to neutral, so mixing should be effortless with these.

Final Rating

6
With Sonarworks Reference 4
Calibration Enabled
6.1
Without Sonarworks
Calibration

Remove coloration from your
headphones with Reference 4

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