Review written by Andrew Park (Resolve)
The headphone in this review is a demo unit sent by Audeze for evaluation.
Over the past year, Audeze has released a number of ultra high end products, like their planar flagship LCD-5, which received quite a bit of praise from me and others from within the audio community. Now they’ve had some of their new high end tech and design concepts trickle down into a more modestly priced (yes, they are still expensive) headphone in the form of the Audeze MM-500. Why MM-500? What is MM-500? ‘MM’ stands for Manny Marroquin, who I’m told is a well-respected and award winning mixing engineer, and now gets the high honor of having collaborated with Audeze on a headphone.
The new Audeze MM-500 comes in at $1699, so it’s in the ballpark of the HiFiMAN Arya Stealth, the Sennheiser HD 800 S, and a number of others that make it a competitive price bracket. Importantly, Audeze’s own LCD-X sits at $1200, and so in this review I’m taking a look at the MM-500, to see how it stacks up.
One thing to note is that Audeze are also clearly going after the pro market with this headphone, and while I think it’s an interesting question as to whether this is the type of product that would be optimally suitable for a studio environment (in particular with the kind of tuning they’ve gone after here), I’m approaching this more from the point of view of the enthusiast or “high ender”. I want to give a sense of how this might be received by anyone looking for a headphone with awesome sound quality at this price point, and won’t be addressing the ‘pro use’ question - the idea of using it as a tool - in this article.
As a reference point, for this review I was using the MM-500 off of several different amplifiers, but primarily out of the Vioelectric HPA-V550 headphone amplifier and Matrix X Sabre Pro for the DAC. I also tried it out of the SPL Phonitor X, the THX AAA One, Ampsandsound Kenzie, but consider the HPA-V550 setup as the ‘reference’ here.
Just so you're aware, the MM-500 has a reasonably high sensitivity and doesn't require much in the way of amping to get it loud enough, so you should be able to run it from most devices.
- Style - Over-ear, open-back
- Transducer type - Planar Magnetic
- Magnetic structure - Fluxor™ magnet array
- Phase management - Fazor™
- Magnet type - Neodymium N50
- Diaphragm type - Ultra-Thin Uniforce™
- Transducer size - 90 mm
- Maximum SPL > 130dB
- Frequency response - 5Hz-50kHz
- THD <0.1% @ 100 dB SPL, 1kHz
- Weight - 528g
- Reasons to buy
- Smooth sound signature with relaxed treble and a rich, mid-forward presentation
- Good planar magnetic headphone performance all around
- Looks amazing with exceptional build quality
- Very different sound compared to older Audeze headphones
- Reasons not to buy
- Clamp is a bit tight on larger heads
- Slightly hot upper midrange
- Very different sound compared to older Audeze headphones
Build, Design & Comfort
The Audeze MM-500 takes inspiration from the company’s latest flagship LCD-5 in its design, with a few changes along the way. This means the MM-500 does away with the massive cup designs of the older Audeze headphones and instead makes use of a much smaller, lighter and more compact design.
With that said, the MM-500 is still on the heavier side of things, coming in at around 500g. That’s because instead of a carbon fiber headband, the MM-500 uses metal, and instead of the resin cups of the LCD-5, the MM-500’s are metal all around.
In practice this is one of the best looking headphones I’ve ever come across, and it feels incredibly well built. In fact I’d go as far as to say the MM-500 is the new high benchmark for build quality in a headphone at this price, and it has that kind of extra regular but great design aesthetic that really speaks to me. In a landscape where most high end headphone designs aim for overly flashy and eye-catching exteriors, the MM-500 achieves a more sleek yet subtle industrial design, which is ironically what makes it stand out from the rest. It just goes to show that you can make an exceptional looking headphone while still using black, muted and metallic colorways.
It’s not all great, however, and unfortunately for me personally there are a number of ergonomic and mechanical concerns. Simply put, with the current headband, I find it uncomfortable for my larger than average head.
Just like the LCD-5, the MM-500 has substantial clamp force for those with larger than average heads. This is in part a requirement for the type of mechanical assembly Audeze have gone for with this headphone, with the way the rods create the necessary angle to keep the cups in place on the side of the head to create a seal. You wouldn’t want it to be too loose, because then that seal gets compromised and has an effect on the sound, but I find that with this new headband system, as much as they look amazing, the clamp is just too strong for my head. I think it would've even been better to stick with their previous headband design.
Thankfully, there is somewhat of a solution. An Audeze representative has indicated that the MM-500’s headband is springsteel and this means that there is an opportunity to stretch it out over some books or blocks and have it loosen the clamp over time.
Since this is my primary complaint with this design, I tried it. Sure enough, it did loosen the clamp a bit, but I still wasn’t able to make it comfortable for longer listening sessions, and I really think it would be beneficial to use either a lower clamp force headband design, or offer a longer top piece to accommodate larger heads - which is something Audeze has already done with their LCD-5 design. The point being that in my view, while it’s close, it’s still not enough to accommodate big-headed audiophiles like myself.
But of course, for those with average or smaller heads, this shouldn’t be a problem at all.
For the pads, they're a different shape to those found on the LCD-5, but still with a decent amount of space inside for ears. I think there may have been some pushback on the use of adhesive pads, especially in comparison to the clip-in style found on other headphone designs like from HiFiMAN, but Audeze has an excellent post on this topic, explaining why this is necessary for sound quality purposes.
And they're right, with the way these transducers are designed, if there were any seal imperfections between the pad and the housing, it wouldn't be possible to achieve deep bass response - and in recent headphones I've evaluated that use porous velcro pads you see exactly that missing.
If you're wondering, HIFiMAN designs are able to use clip-on pads and avoid this issue in part because their drivers are truly enormous, and there are still further ways of circumventing this issue that Audeze could've gone for. But, sealing the pads on with adhesive is a fine solution to the problem, and one that doesn't compromise on sound quality, which is nice.
The following is how the Audeze MM-500 measures on the GRAS 43AG with anthropometric pinna relative to the combined version of the Harman preference target (2013 bass, 2018 mids and treble). This is a smoothed reference point that's suitable for most listeners looking for an even spectral balance from their headphones.
How do you read this? The dotted black line is the target (the reference point), and the colored line are how the headphones in question measure. Effectively, this shows the headphone’s frequency response in relation to a known reference point. It’s important to note that because the target is highly smoothed, there are places where deviation is required (like at around 9khz for example).
Like the LCD-5, the Audeze MM-500 goes after Audeze’s new style of sound, which is a massive departure from their older tunings. Fans of their older sound might not be as into this one, but for those who may not have been into Audeze headphones in the past as a result of the lack of ear gain and upper mids (an important critique), should consider this one more seriously - and indeed all of Audeze’s newer headphones.
Based on the frequency response measurements of the Audeze MM-500, you can see that they’ve gone for a generally neutral to mid-forward kind of sound signature, and one that slightly emphasizes 3khz over the resonant harmonics in the treble above, but just ever so slightly. In many ways, this headphone is the closest in tuning to the legendary Sennheiser HD650 and HD600 series of old, just in high-end planar magnetic form, which lends a few benefits.
The first of which is the full bass extension down to 20hz you see here, which is great. There is a slight emphasis to the lower part of the ear gain around 200hz, causing a general kind of richness and warmth to the sound, but not in a way that overpowers or drowns out the midrange. And, as mentioned, it’s the midrange that I find to be slightly emphasized with this headphone. This is also because of the relaxed treble as well.
It’s important to note that when looking at a frequency response graph, it’s all about understanding the relative balance among different frequency ranges, and with the MM-500, you get a mostly good result for the balance between fundamental tones and their resonant harmonics in music, just with one quirk that I'm going to nitpick.
On certain recordings, the emphasis to the upper mids can cause a slight amount of glare, and if you think you’re sensitive to this region, that’s definitely something to keep in mind. Really, this is where I think the strongest critique of the MM-500's sound signature should also be directed, if there is one to be had at all - certainly it's an important discussion point surrounding Audeze's new tuning approach. It's like they went so strongly in the opposite direction of their previous targets that they may have overdone it by just a hair, for me at least.
At the same time, there are some recordings where I found this forward character to the midrange presentation to be more acceptable, especially for tracks with lots of instruments. It’s also not as emphasized in that region compared to the LCD-5, and is quite similar to the HD650 for the relationship between upper mids and treble, and if you found that to be enjoyable you’ll likely be into the MM-500 as well.
Importantly, the MM-500 also handles treble better than the LCD-5, as I find it to be a bit smoother. This is something that high end planar magnetic headphones often struggle to do well, and in some ways is responsible for some reports you may have read about planars not sounding particularly ‘natural’. The MM-500 does a good job as a counterpoint to those statements, as its treble is relaxed, yet well extended, and doesn’t have that kind of artificial treble quality that often gets attributed to headphones with this type of transducer.
In general, I’m going to go out on a limb and say that the Audeze MM-500 is one of the best tuned Audeze headphones to date - at least for the high end ones, and I like that they’re going in this direction.
As mentioned, if you’re considering this one based on narratives of how Audeze headphones have sounded in the past, know that the MM-500 is very different sounding to those older ones. Yes, it is more ‘objectively’ correct compared to those, but those older ones also have a vocal fanbase who love that kind of sound. So just keep in mind that the MM-500 is very different.
For my own preferences, while I still find myself using a touch of EQ with this to reduce the upper mids, by no means would I say it’s required, and I think on this one it’s even less of a requirement than what I found with the LCD-5.
Now let’s get into how the MM-500 sounds subjectively. As always, while it’s potentially possible for the following descriptions to all be understood in terms of frequency response at the ear drum, there are simply qualities of the experience that can’t yet be fully predicted by the graph alone, and so I’m going to do my best to describe the way it sounds to me.
When it comes to the MM-500’s ‘technical performance’, or in other words, all of those descriptions that us nerdy audiophiles like to give, I find it to be in a similar league as that of the LCD-X 2021 - that is to say, generally solid. With that said, I also find it to be differently technical.
The MM-500 for example sounds a bit tighter, more controlled during busy passages, with a bit better image separation and distinctness compared to the LCD-X 2021. At the same time, I also find the LCD-X 2021 to have longer lasting trailing ends of tones. That’s not to say that the MM-500 sounds particularly dull or blunted, but rather it just gives a slightly tighter and more controlled presentation of the images. This is actually something I really enjoy about the MM-500 over the LCD-X.
For soundstage and sense of space, the upper mid-forward character has a tendency to bring the whole presentation more in front of me, and less spaced out to the sides. But it’s also not overly claustrophobic despite its more intimate tonality, and it images with precise, incremental gradations of position without any smearing or blobbing going on (where it sounds like music is only coming from only a few limited locations in front of you).
To me it sounds less like a bubble that goes all the way around your head, and more like a bubble that’s in front of you that starts midway through your head. With that in mind, I’d describe the MM-500’s soundstage as nothing more than ‘acceptable’, and those looking primarily for a sense of spaciousness in their headphones should consider the HiFiMAN Arya or the Sennheiser HD 800 S instead.
For dynamics or the sense of punch and impact, this quality is not the MM-500’s strength - at least not the way that it is on something like the original HiFiMAN HE6 - and it’s not something I typically find in planar magnetic headphones. But with that said, it’s also not overly dulled in that regard either, and notes have a satisfying weight to them. I think, for those who are uniquely looking for this quality, you’re still better off looking at dynamic driver moving coil headphones, as they tend to more commonly exhibit this characteristic, and the MM-500 isn’t something that subverts that trend.
Lastly, for the question of ‘timbre’, the MM-500 doesn’t suffer as much from some of the treble ‘plasticky’ quality that can sometimes come with high end planar magnetic headphones, and while I also expect this to be something captured by frequency response, it’s difficult to say exactly what causes it. Nonetheless, I expect the reason the MM-500 sounds a bit more natural is because of the more subdued treble presentation overall, once again not unlike the Sennheiser HD650.
Of course, it is still recognizably a planar magnetic headphone, and in that sense it’s not going to unseat those Sennheisers for timbre, or you may also consider certain biocellulose dynamic driver headphones if this is a key requirement.
The LCD-X 2021 is much improved over the previous version for its tuning, especially throughout the midrange, and we can think of it as a generally balanced sound with a somewhat laid back character to it. It also has a bit of an upper treble boost, meaning it’s got a decent amount of ‘air’ or ‘shimmer’ to it, and also ensuring that no lower harmonics are emphasized over the upper ones.
With the following comparison you can see that forward character I mentioned is in the exact spot where the LCD-X 2021 is more withdrawn. So in a way, it’s a pick-your-poison kind of situation there, even though they both have their strengths.
I've aligned these averages at 1khz, which makes the lower mid and bass sections look more significant, but for relative balance they do sound like that, and at least this shows alignment at mid-treble as well.
In many ways the MM-500 is the more ‘correct’ tuning, but it’s also less forgiving on recordings in the upper mids. By contrast, the MM-500 is also more forgiving in the treble. Personally, I’d love it if they aimed for something in between, but I can see both tunings being enjoyable for different listeners.
As far as overall sound quality is concerned, I have a hard time saying the MM-500 is a significant step up from the LCD-X 2021, they’re just categorically different. At the same time, it would be a mistake to say that Audeze hasn’t improved the tuning of their headphones with this new direction, and I can certainly see listeners chasing ‘correctness’ appreciating the MM-500 more.
This is an interesting one. The LCD-5 and MM-500 measure very similarly to one another, and straight up, I prefer the MM-500 tuning. While I really appreciate the new sound that Audeze is clearly going after with their recent releases, and in fact the LCD-5 is probably the flagship headphone I’d buy today if I could afford one (or at least high up on the shortlist), it’s still one that I feel the need to EQ.
With the MM-500, It still has a touch of that glare on certain recordings, but it’s simply not as noticeable due to the treble above it having more presence than the LCD-5. It's subtle, but it makes a difference.
Now, with all of that said, make no mistake, the LCD-5 is still an important step up when it comes to technical performance, and it’s quite clearly more impressive for sheer resolution and separation. This is also what makes it all the more interesting to compare these two, and to see just how closely they measure to one another - and yet how wildly different they sound for some of these qualities!
I expect that the frequency response at the eardrum is actually more different than what it indicates on the GRAS rig, because these types of front-sealed (open back) planar magnetic headphones create a system with the eardrum, and without using probe mics at the eardrum it’s difficult to tell what the frequency response differences are in practice when coupled to the side of an actual human head.
The MM-500 is much warmer and more mid-forward compared to the HiFiMAN Arya, which I’d describe as a more treble-focused presentation. Both have full bass extension, but the Arya’s bass is also a bit stronger, and this is also bound to elevate a bit more as a result of it having a much lower driver resonance frequency. The elongated cups mean that in most cases there isn’t a perfect seal, and this incurs an air gap and elevates the bass ever so slightly.
I think of the differences between these two like this, the Arya is like a planar HD800s, while the MM-500 is like a planar HD650 (and yes, I’m aware the HD 800 S is much more expensive but the HD600 and HD650 are truly legendary headphones and arguably have a more natural tonality). Both have their strengths and weaknesses, and depending on the kind of presentation you’re after, I can see either one being preferred.
Apart from my complaints with the clamp force that make this headphone mildly incompatible with my life-long affliction of large head syndrome, and that I expect this to be a problem for other similarly large-domed audiophiles, I’m going to recommend the Audeze MM-500 - that is, if you know what it is that you’re getting into!
It’s important to know that the sound signature here is very different from Audeze’s previous releases. It’s technically ‘better’, but there are fans of that older sound who may have certain expectations. Categorically, the MM-500 is not that flavor, however in my view this is yet another step in a positive direction for Audeze, even if fans of their older sound will likely still prefer the LCD-X 2021.
Personally, I’d like a bit less upper mids and a bit more treble to balance out what is a key ear gain transition point a bit better, and in that sense I’d probably go for the HD 800 S or Arya Stealth instead. But, if you love mids and want to bring all of that tonal richness forward, the MM-500 does exactly that, and it does it well. With this one, you get the closest headphone yet to a high end planar magnetic Sennheiser HD650 - and that’s not only unique, but something many listeners have been actively searching for.
Lastly, while other less expensive headphones like the LCD-X 2021 and Arya Stealth still represent better overall value when it comes to sound quality, Audeze’s attention to build quality and industrial design here is a cut above those, and it's worth taking that seriously. Just... please make a larger headband so I can love it too.
-Andrew Park (Resolve)