The Land of the Rising Sun is responsible for bringing us some of the best audio gear around. Japanese companies known for the impeccable quality and value of their electronics produce everything from killer XLR cables, to microphones, to the subject of this comparison – monitoring headphones for music and audio production. The Japanese conglomerate Audio-Technica is highly-revered among these massive corporations. Their AT series condenser mics provide phenomenal value for their price. And their ATH series monitoring headphones are no strangers to this idea, either. In this ATH M40x vs M50x comparison, we’ll cover all of the data and information you’ll need to know about for these two headphones. Frequency response curves, technical specs, pros and cons, and some key differences are all important things to consider if you’ve got your hands on your wallet. We wrote this guide to serve as a convenient comparison between the two. Let’s take a look.
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While the M40x does have the smaller price tag vs the M50x, Audio-Technica didn’t skimp out on the materials and build quality. The M40x and M50x look almost identical, and that’s because they utilize much of the same design priciples.
The M40x uses copper-clad aluminum wire in each voice coil of their 40mm drivers. Designers use CCAW to reduce the weight of the voice coil while still maintaining a high degree of conductivity. The bottom line is this – a lighter voice coil leads to more precise movement of the diaphragm, and therefore a more accurate reproduction of audio.
Audio-Technica chose neodymium magnets for the M40x. This is a quality choice because of the properties of neodymium. The best headphones will use magnets that are very light and also have a strong and long-lasting permanent magnetic field – neodymium magnets deliver all of these.
Closed-back headphones are designed for sound isolation. Both the M40x and M50x are closed-back, meaning they’d work well for an artist or vocalist during recording.
It’s worth noting that for mixing and mastering, open-back headphones are usually the better choice due to their superior imaging and soundstage. But the closed-back nature of the M40x does the job well enough and still provides us with the flexibility to use them in and out of the recording booth. If you’re producing audio in a less-than-ideal acoustic space (a bedroom, for instance) then closed-back headphones will help due to their superior sound isolation.
Driver size is an important distinction to make between the M40x vs the M50x. The M40x has a driver diameter of 40 mm, falling 5 mm short of the M50x. This may not seem like a big deal, but that extra 5 mm is what really sets these two apart in price and performance.
As a general rule of thumb, a larger driver diameter usually means better bass reproduction. If we think about the size differences between a subwoofer and a small tweeter, and the frequency ranges each is used for, it all begins to make sense.
The M40x is foldable and the ear cups also swivel 90 degrees. This makes them handy for those of us who are both producers and DJs, and helps save space when traveling on the road for gigs. The M40x also comes with a soft carrying pouch to protect from scratches and other cosmetic damage.
The M40x uses high-strength plastics for the housings. The headband is made of springy metal (looks like stainless steel), striking a balance between strength, flexibility, and weight reduction. The headband on the M40x appears to be slightly thinner than the M50x.
The stock ear pads are a cheaper memory foam, and some users say they aren’t very deep or comfortable and even effect the sound of the headphone. Aftermarket Brainwavz ear cups are a decent alternative if you want to upgrade the stock ear cups on the M40x.
At first sight it’s very easy to mix these two up. But with a little more analysis, it’s clear that there are a few small details between the M40x vs the M50x among many similarities. Let’s get a look at what these are.
The voice coils for both headphones are made of the same material – copper-clad aluminum wire. Like we hinted at earlier when talking about the M40x, CCAW is a great material choice due to it’s low weight in comparison to solid copper wire. Less weight means finer precision movement, and translates into better audio.
Sometimes, manufacturers will use thinner wires to reduce weight, but it seems like AT didn’t decide to go this route because the impedance of both the M40x and M50x is still relatively low. Thinner wires mean more windings, and this usually results in a higher impedance rating.
Just like the M40x, the M50x utilizes permanent rare-earth neodymium magnets. These are more than enough to provide light-weight, long lasting performance out of both headphones.
The M50x is also a closed-back headphone. While not ideal for mixing or mastering, they do a good enough job given the price while allowing for versatility in the studio. Both the M40x and M50x will be well suited for monitoring applications during recording as they are good at blocking out ambient noise.
The M50x also has surprisingly-good stereo imaging for a closed-back headphone, while the soundstage for both the M40x and M50x may leave something to be desired.
It’s time to talk about the biggest and possibly most important difference between the M40x vs the M50x. This is the driver size.
The M50x has 45 mm diameter drivers which are 5 mm larger than the M40x. Frequency response testing has shown this to make quite a difference in the low-end sound of these two similar headphones.
According to data from RTINGS.com, the M40x has a more exaggerated bass response between about 100 Hz and 250 Hz, with a steeper bass roll-off past 30 Hz. Some users say the M40x is a better casual listening headphone than a monitoring headphone for its warmer response.
The M50x inevitably has a less hyped bass response perhaps due to the larger drivers which are more capable of handling lower frequencies with a higher degree of accuracy.
Both the M40x and M50x are folding and swiveling headphones. One key difference here is the degree of swivel, though. The M50x ear cups are able to swivel a full 180 degrees vs the M40x which can only swivel 90 degrees.
The M50x also uses quality plastics, metal, and fleather to achieve a decent degree of build quality.
The headband seems slightly thicker on the M50x vs the M40x, and it’s extremely flexible. It’d be difficult to find a person with a head that’s too big for these headphones.
The build quality and design between the M40x vs the M50x is nearly identical. It’s hard to tell the two apart if you don’t know what to look for. They’re both made of high-strength plastic, flexible metal, and premium materials that should be expected from anyone who’s used Audio-Technica products before. Both are dynamic moving-coil type headphones with copper-clad aluminum voice coils and neodymium magnets. They differ slightly in driver size, however.
Specs for the ATH M40x vs the M50x are very similar, with a few key differences to point out which are outlined below:
Independent frequency response testing seems to vary somewhat from site to site. Headphone testing presents some tough challenges that aren’t always easily solved.
That being said, the tested frequency responses for both of these headphones are quite similar as we can see below from testing done by RTINGS.com, a great site for headphone reviews and other helpful test data.
Starting at the high-end of the spectrum, we can immediately see some big differences between the two in the 12 kHz to 20 kHz range. The M40x has a prominent peak at 14 kHz while the M50x has a large cut at roughly the same frequency. This will drastically change the way these two headphones sound when reproducing audio in that range.
Traveling further down, the headphone response curves more or less track each other, with some slight deviation in the mid-treble region. The M40x definitely shows a beefier response in that area.
Both experience a large dip at roughly 6 kHz, followed by a moderate peak at roughly 4.5 kHz. This moderate peak is definitely higher in the M50x vs the M40x.
From here, we see some more deviation in the 1.5 kHz to 3 kHz range, with the M40x remaining relatively flat while the M50x shows a peak at 2 kHz.
Further down between roughly 400 Hz and 1 kHz, the M50x hugs the 90 dB SPL neutral axis with another very flat region, while the M40x sees a slight cut in this range and remains below 90 dB SPL.
Both headphones then see a dip between 300 Hz and 400 Hz and then a large, widened peak between 100 Hz and 200 Hz. The bass peak is more prominent in the M40x which aligns with some reports from users that the M40x has a bassier response in comparison to the M50x. From here we see a gradual bass roll-off from 30 Hz and onward.