The past couple of weeks saw me clearing out some of my used but excellent condition audio gear in preparation for new gear. I do make it a point to clear our some old stuff before picking any new items. Given I am in Asia, November is the time of the year to pickup just about anything with the deepest discounts on 11.11 Singles Day and of course Black Friday Sale. I got through 11.11 just fine and next up is BFS on Nov 27.

The Audio-Technica ATH-M40x was top of my list to replace my 6 year old Sony MDR-7506. There is absolutely nothing wrong with the Sony. Yes, I did go through 3 earpad changes over the 6 years (averaging 2 years each) but other than that, the MDR-7506 still rocks. It is lightweight, very compact when folded and has shown itself to be extremely durable under most conditions. Would I still recommend the Sony MDR-7506? For sure I would if any of the above I mentioned stacks up high on your criteria.

So why the Audio-Technica ATH-M40x? It came done to just 1 thing really; flat frequency response. The MDR-7506 are great in that respect. They have been trusted by professional sound engineers in and out of studios for more than 40 years. For the $89 USD I paid for the Sony MDR-7506, they were cheaper than the popular Audio-Technica ATH-M50x for $169 USD on Amazon. However, in recent years, Audio-Technica released their M40x, M30x and M20x as alternative offerings to the M50x. The M40x is the M50x killer here and it is no secret.

The M50x by default has a boosted bass response. While many folks like that extra thump, I picked the MDR-7506 over them as I wanted a flatter frequency response. Enter the M40x intentionally tuned to provide a flat frequency response. The M30x are bumped to provide better mid-range clarity if that is something you prefer. The cheapest M20x offering provides an entry point to much acclaimed ATH-Mxx series of Professional Monitor Headphones by Audio-Technica. Check out the video below to find out more about the 4 different ATH-Mxx series headphones.
Since I no longer have the MDR-7506 with me so I will not comment on difference in sound signature. I will say 1 thing however, watching the video above in 1080p on my MDR-7506 vs. the ATH-M40x, the differences in sound was more prominent on the MDR-7506. I think that had to do with the slightly boost top end on the MDR-7506 and the fact I had velour replacement earpads on. For some, that is a good trait especially where you are trying to pick of details in your mix. The ATH-M40x will probably be less ideal if that is what is important for you. I will link to another video below which I think sums up how they both compare to the Sennheiser HD280; another pair of well reviewed professional studio monitor headphones. For the rest of my review, I will focus on build quality and highlight key differences between the MDR-7506 vs. the ATH-M40x.
Weighing in at 240g, the ATH-M40x is a shade heavier than the MDR-7506 at 229g. You might wonder if that 10g makes a difference on your head. I will tell you that in the case of both these headphones, you will feel the difference. The ATH-M40x feels much sturdier when it comes to build quality. Perhaps my pair is less than 12hours old but the earcups range of motion on articulation and swivel feels tighter than the MDR-7506. There are clicks as I manipulate the positions of the earcups on the ATH-M40x. The MDR-7506 did not have the clicks and ticks but had a springy action especially when collapsing the earcups as you folded them up for storage or traveling. I do prefer the MDR-7506 in this area compared to the ATH-M40x. Perhaps over time, I will get accustomed to the new ATH-M40x but for now, I am cautiously handling the headphones and have a weird feeling they are a taunting pair out to wrestle me.

Comfort wise, I give it to the MDR-7506 hands down. Both feature 40mm Dynamic Drivers meaning the earcup and earpads sizes do not detract too much. Frankly, the original earpads that came with the MDR-7506 do not hold-up in the longevity depart. Yes, they are fairly comfortable but breakdown in about a year’s time. The MDR-7506 came with On-Ear pads. You could replace them with slightly larger pads but I found doing that alters their sound signature quite significantly mostly due to the change in driver distance to your ear canals.

The ATH-M40x original earpads are just a smidge bigger but not big enough to be Over-Ear for me. I’m sure they would be for my daughter. The foams pads however feel a little hard on the ears and this is on top of higher clamping force compared to the MDR-7506. I did pickup a pair of replacement earpads before I even ordered the ATH-M40x. The $5.00 SGD are far from anything fancy but I am happy that they are just slightly bigger hence making the ATH-M40x Over-Ear for me, rather than On-Ears. The thickness of the pads are close enough hence maintain similar distance from the drivers to my ear canals which is ideal.

The other thing about the ATH-M40X is the shape of the headband and padding. This might differ for you but the ATH-M40x rested squarely on the top of my head. The padding on the underside of the headband was quite frankly a joke. Made with thin foam, I felt the steel headband at a singular pressure point on the top of my head. The full weight of the ATH-M40x rests squarely on that spot, no two ways about it. Although the MDR-7506 had literally zero padding on the underside of the headband too, the curvature of the headband distributed the weight of the headphones evenly so it doesn’t feel like my head was a headphones hanger. The clamping force is lighter in the MDR-7506. Solely on headband curvature and clamping force of the earcups, the MDR-7506 allows for extending studio sessions. I will have to find headband covers for the ATH-M40x before they give me a headache. Short end of it, the MDR-7506 are superior in terms of comfort out of the box.

Accessories side of things, I will tell you that the MDR-7506 came pretty bare. You got the headphones, a storage bag (mine was hard pleather which crack and died) and a screw-on 3.5mm to 6.3mm adapter. The other end of the coiled cable was fixed to the left earcup. For some folks, that is an immediate deal breaker. I would prefer a detachable cable perhaps but given the MDR-7506 are so compact when folder, I honestly do think it will not be much issue once you stick them in a storage bag. I never missed detachable cables in them.

The ATH-M40x had a storage bag in the box, a screw-on 3.5mm to 6.5mm adapter (yay! I love screw-on) and 2 detachable cables. 1 straight super long (3m I think) cable and another coiled cable which I love and found to be the most versatile except for when you are commuting. The M50x includes an additional 1.2m ‘short’ cable with the M40x does not include in the box. I doubt many will be using the include ‘long’ straight cable but if you are thinking of getting aftermarket replacements, there is a twist – literally.

First off, the ends of each side of the cable are not the same. Well one end features your standard 3.5mm plug, the end that connects to your left earcup of the ATH-M40x is 2.5mm. Sure, 3.5mm would be better but there are 2.5mm cables out there too yes? Well, it depends. Because Audio-Technica uses a proprietary twist lock feature on the ATH-M40x (and a lot of their headphones), you have 2 choices around aftermarket cables. You could source cables that feature the same twist lock feature or, you could open up the left earcup and remove that lock mechanism.

Frankly, I am not too bothered by it at this time since I will only be using the coiled cable. If you need a ‘short’ straight cable for commuting, either shell out money for an overpriced original cable from Audio-Technica or you have 2 options as mentioned above. If it was for me, I would just go the cable route and skip removing the twist lock mechanism. In about 2-3 years time, I might but not when it is under warranty cover right now.

Should you get the Audio-Technica ATH-M40x or the Sony MDR-7506? If you are asking that question, I would say it depends on what is more important for your use case. I use my Monitor Headphones indoors for critical listening and when I digitize my vinyl records. Detachable cables are not really important for me but I value coiled cables that are able to extend up to 3m when I need to reach across the room. Both the MDR-7506 and ATH-M40x are able to do that. My decision on the ATH-M40x was its stellar flat frequency response. The MDR-7506 are excellent in that department and if it’s not as critical for you to have a totally flat frequency response, I think the MDR-7506 is definitely worth considering. They usually go for about $10-20 USD cheaper on Amazon when on sale but their biggest advantage is comfort.

The MDR-7506 simply put knocks the ATH-M40x over when it comes to overall comfort and extended use. You could swap to slightly larger earpads so they become Over-Ear if that matters to you. In fact the $5.00 SGD replacements I got for my ATH-M40x are supposed to fit the MDR-7506 too so that the least of your issues. The MDR-7506 are very compact and lightweight but extremely durable. Mine lasted 6 years without any major issues. I still don’t know how longer my new ATH-M40x will last me – I will let you know in 6 years time if they are still working.

Decide what holds priority for you. I really do not think you can go wrong with either of these 2. For flat frequency response for mixing or tracking and detachable cables go with the Audio-Technica ATH-M40x. For comfort over extended periods and almost as stellar frequency response, the Sony MDR-7506 are trusted by professionals for more than 40 years now and continue to be a staple in good recording studios. I had the ATH-M40x on my head for about 30mins this morning. 180mins in, I am still feeling that pressure point on the top of my head. I hope this post has been helpful for you. Let me know what thoughts you might have.
