Moondrop Horizon Review: None More Dark

Moondrop is best known for dominating the budget IEM sphere for the last half-decade or so, but in more recent times they’ve also put out a few over-ear headphones, nearly all of them being planar magnetic designs. But their newest Moondrop Horizon is the first dynamic driver headphone of theirs I’ve gotten a chance to test, and for its $200 asking price, I’d be lying if I said I wasn’t rooting for it.

I’m typically not a fan of planar magnetic headphones due to their predisposition to upper treble brightness, which means I’ve not been super thrilled with Moondrop’s prior efforts in the over-ear headphone space. However, there was one exception: their most recent effort, the Cosmo, was a headphone I quite enjoyed precisely because it had a more relaxed approach to treble.

It seems that Moondrop may have paid attention to the positive reception the Cosmo got from reviewers like us and Super* Review, because the Horizon also takes a relaxed approach to treble… but they may have gone too far with this one.

While there are a few things about Horizon I like more than Moondrop’s other headphones, I do have to be upfront and say that it didn’t fix my biggest issues with the other designs, and Horizon has a few weird idiosyncrasies of its own that I think will preclude it being a strong recommendation from any reviewer, myself included. Let’s talk about why.

Build, Comfort, Design, and Accessories

Starting with build, the Horizon is middle-weight headphone at right around 350g, but despite what seems like an all-metal build (aside from the pads and headstrap adjustment), I wouldn’t say it’s the most rock-solid build. The chassis itself makes some sticking noises when the headphone is placed on the head/removed from the head, and the overall assembly feels “headband-heavy” instead of “cup-heavy” in a way that makes the headphone seem a bit insubstantial.

Speaking of which, let’s talk about comfort, where despite it being a fairly reasonable weight, Horizon is really quite bad for me. The headstrap itself is actually great (flexible, conforms well to the head, no hotspots), but they did not fix the issue that also exists on the Cosmo where the overall headband is just absolutely gigantic. I have to wear the Horizon on the smallest setting, and even then it’s a little bit too big for me, and the clamp is incredibly gentle. Gentle clamp is usually a nice thing, but here it’s a big problem.

Pairing the overall hugeness with the lack of clamp means Horizon feels incredibly slidey and insecure on my head, such that I have to constantly monitor the angle that my head is rested at to actually listen to the headphone. Unsurprisingly, this balancing act completely takes me out of the zone, and kinda ruins my ability to enjoy the music. The worst comfort experiences are the ones where you’re constantly reminded that you’re wearing a headphone, and Horizon fits that description to a T.

The last comfort nitpick is that the earpads themselves—while likely acoustically necessary for the sound they wanted to hit—are a bit scratchy and too small to fit truly circumaurally for me. However, the biggest annoyance is that either the internal foam or an internal wrapping material causes the pads to crinkle very audibly when you move your head. It’s not something you’ll hear if you’re listening to low dynamic range music, but if the music is paused you will hear it if you move, and this contributes further to the feeling that this is a very cheaply constructed headphone.

Touching on design, visually I think the Horizon looks awesome. I love the black colorway, and I love the grille design that allows for complete transparency to peer into the rear of the headphone and see the driver. I love basically everything about this headphone’s visual design except for how huge and Cyberman-like the headband is when you’re wearing it. The visual design is the only part of this headphone that I would say punches above its asking price, looking more luxurious than its price would suggest.

While the usability of this design needs work, there is at least one good cue that this headphone takes from the Cosmo that preceded it: Horizon keeps Cosmo’s pad mounting mechanism, which includes a magnetic pad mounting ring that can be placed inside an earpad to adhere the pad magnetically to the baffle. This also allows for extremely easy pad removal/swapping, and I think this system is very smart. Moondrop deserves some credit for coming up with this idea and continuing to use it on newer, less expensive designs.

However, upon inspection people will notice that the front damping foam placed in the pad (ostensibly used for tuning the headphone) is incredibly thick. I can’t remember the last time I encountered front damping foam quite this thick, and this matters for the sound, so we’ll discuss this later in the article.

Further commenting on the design choices here, I don’t love the headband adjustment mechanism—it clicks very forcefully but because the piece is a very simple plastic, this strikes me as the first part of the headphone that is likely to break. Additionally, within a few adjustments it will visibly scratch the black paint(?) of the out-facing part of the headband adjustment slider.

And lastly, in terms of accessories you basically just get a 3.5mm cable and an included 4.4mm adapter for it. The cable itself is fabric-wrapped and reasonably compliant, but there’s definitely a bit of shape memory that precludes me wanting to use it over one of the softer, less memory-prone cables I have around. It’s not terrible by any stretch, and I like that it comes with a chin cinch (kind of like an IEM cable), but it’s just not quite flexible or soft enough for my taste.

Overall, Horizon is an inexpensive (though perhaps expensive looking) headphone with simple accessories package and a pretty terrible comfort and build profile. While this design has cool aspects like the pad mounting mechanism, I really wish Moondrop would just move away from this headband design already, as it’s the obvious weak link in the chain here. The pad crinkle is also annoying enough that I basically never want to put the headphone on my head, let alone listen to it, and the fact that the headstrap adjustment mechanism scratches itself just from use is pretty inexcusable.

Sound

This headphone is interesting, because at first it doesn’t sound disastrously wrong, but with a bit of listening it reveals itself to sound minorly wrong, but everywhere. It has issues from top to bottom, and it’s arguable that within this rollercoaster of a response there is still a semblance of overall balance, but it’s absolutely not what I’d call “normal sounding.”

Let’s start with the bass because it’s actually where I have the least issue. Horizon is an open back dynamic driver headphone, so a little bit of rolloff is to be expected. Personally I’m not a huge stickler when it comes to bass amount—in fact I tend to prefer linear extension with no bass boost at all—so the rolloff here doesn’t present many issues for me, especially because of how it balances with the treble.

Kick drums are lacking a bit in size and decay, trending towards a snappier, leaner presentation than a thick or powerful one. Bass guitars sound fairly even until they get to their bottom octave where it becomes a bit noticeable that their overtones are starting to dominate the fundamentals, leading to basses sounding a bit more nasal and honky than they would with proper extension.

Speaking of honky, the bass’s integration with the midrange is a bit confusing because it technically doesn’t have any disastrous issues, but there are a few colorations that still stop the Horizon from earning the “neutral” descriptor from me. The three main colorations are an extra sense of bloom around 200 Hz, a bump around 1 kHz, and a relaxed 2-5 kHz region.

The extra 1 kHz is definitely noticeable, for good reasons and bad. For piano recordings, this extra overtone presence actually helps what can sometimes be an overly-soft instrument sound much more clear and present, but it also can cause guitars and bowed strings to sound a bit too cacophonous, almost as if they’re mixed too loud overall.

The other issue with the midrange is that there’s a warmth that arises from both the 200 Hz bloom and the relaxed 2-5 kHz region, which causes voices to sound simultaneously clenched (due to the 1 kHz rise) but also muffled and blurred. Adding all of this together means that Horizon’s midrange has a mix of “high energy” and “low energy” colorations that don’t really balance each other all that well, causing it to sound confused and disjointed instead of well-integrated.

And lastly, the treble. For many audiophiles, myself included, headphones live and die by their treble response… and this is where the Horizon throws itself off a proverbial cliff and into shark-infested waters. This is one of the darkest headphones I’ve ever heard, such that I’m shocked that Moondrop—a company who typically tunes their IEMs and headphones to be quite bright—are the ones who brought this to market.

To be clear, it’s not unilaterally dark, as there is a peak around 5.8 kHz on my head that is just moderate enough not to become an issue for most things… but above that point, this headphone is missing all of the characteristics that a well-tuned treble response ought to convey.

While vocals retain most of their actual intelligibility due to an intact 2-4 kHz region, there’s no air, breath, or clarity to them. Cymbals’ timbral character is entirely off, leaving them with a strange sense of clackiness that I assume arises from the complete lack of mid treble and upper treble relative to low treble. Acoustic guitars sound like they’re being played at you from behind a curtain or something; all of the directness, sparkle, and percussive precision you’d ordinarily get from an acoustic guitar in a mix just isn’t there.

A treble response that avoids sibilance or overt shimmer is definitely something I want from a headphone, but Horizon absolutely goes too far the other direction, smoothing out and blurring the edges of almost everything with an exceedingly broad brush that makes this one of the most “lo-fi” headphone experiences I’ve had. And as one of the most infamously treble-sensitive reviewers out there, I think it’s clear that if I’m saying it’s too dark… we’ve got a problem.

That said, I do need to acknowledge that their choice to tune the treble like this does actually cohere reasonably well with the bass response, in that both are—subjectively—roughly equally rolled off sounding. If Horizon had a more forward treble presentation, the lack of bass and the leaner midrange would likely be more noticeable. If it had more bass, the lack of treble would sound even worse than it already does.

So as far as balance is concerned, I actually think the Horizon’s balance makes sense, but it still sounds strange, and is very obviously flawed. So for those who are interested in this headphone, know that while it may not be immediately obvious how bad it is because the broad-strokes tonality is balanced in terms of bass-to-treble interplay, it only takes a few seconds for that impression to wear off and for the weirdness of this headphone to make itself known. It is a very dark headphone, so unless you know that’s what you want, it’s probably worth avoiding the Horizon.

Presentation, and Speculation on Acoustic Design

In terms of all of the funny audiophile metrics, I think most people will be able to guess that something with such a dramatic lack in the treble will be unsatisfactory when it comes to detail, speed, dynamics, spaciousness, etc. And they’d be right. Horizon gets failing grades in basically every metric I can think of.

The detail and speed is snuffed out by the lack of treble, the dynamics and transient integrity is muffled by the lack of treble, and the spaciousness is nonexistent due to the lack of treble making everything sound rather claustrophobic and close.

So my main question here is: why? Why was it tuned like this?

Well, my assumption based on the headphone’s design is that they started this project wanting to use an angled driver orientation. Many companies love to advertise that angled drivers have a positive effect on spaciousness or “soundstage”—even though it’s not necessarily true at all—and audiophile consumers often enthusiastically buy into this marketing.

The problem here is that headphones aren’t that simple. When you angle a driver relative to the ear in close proximity like this, you’re going to get a different pattern of contributions from the ear’s anatomy than you would from just having the driver parallel to the side of the head—a different frequency response.

While some people may hear the frequency response differences that arise from this more angled orientation as “soundstage,” what they’re hearing is a frequency response change, not some magical property of the driver being angled by a few degrees.

The typical coloration we’ll see from a headphone with a frontally-placed/angled driver like this is an increase in the low treble, and this (I think) gives us a clue as to why Horizon is so dark. They started with an angled driver, it gave them a bunch of low treble (the 5-6 kHz peak), and the only way to smooth that peak out was by using the incredibly thick piece of front damping foam I mentioned in the Build, Comfort etc. section.

This did damp the lower treble peak enough to be tolerable… but it also had the unfortunate side effect of absolutely nuking everything above this one problematic peak. While for me, a large dip is a lesser sin than a harsh peak, it must be said that if they’d gone a different route with the acoustic design/construction of the headphone itself, this compromise could’ve been entirely avoided.

Comparisons

Sennheiser HD 6XX

This comparison should come as no surprise to anyone, given Herbert Zheng (CEO of Moondrop) said himself that the Horizon was aiming for something “HD 580-like,” but man… I really don’t think this comes close at all to the sound profile of the HD 580/600/650.

The Horizon has even less bass than the already bass-light HD 6 series, which means bass instruments sound even smaller and less powerful than a headphone often criticised for this lack.

Horizon also has a more uneven midrange, eschewing HD 6XX’s upper midrange clarity and lower midrange warmth for something more unnatural and boxy. And of course, Horizon is also way way darker than even the HD 650, which is often regarded as verging on being too dark for many people.

In general, the HD 6XX is usually available at the same $200 price and is built better, is more comfortable, and sounds better in basically any metric I can think of—objective or subjective. HD 6XX has better tone, is more detailed, and is better extended on both ends than the Horizon. So if you want a headphone in this range, the HD 6XX is still the one to beat, and the Horizon doesn’t even really begin to offer a compelling alternative unless you know you want something really dark.

Conclusion

Overall this seems like a fraught release that, much like the Void that preceded it, isn’t going to make waves or find any real audience, because Horizon doesn’t provide anything new or better to consumers in this price bracket who typically care a lot when it comes to getting the most sound quality for their dollar, except for exceptionally large-headed individuals who are also incredibly treble sensitive.

My hope is that Moondrop discontinues the use of this headband because it is absolutely the weak point with all of their headphone designs. I also hope that instead of focusing on things that are essentially marketing-bait like “driver angling,” Moondrop starts their next dynamic driver headphone project with frequency response tuning being the first and foremost consideration. At this price range, it’s easily the most important thing to consumers.

Horizon has really big issues in build, comfort, and sound that other headphones in this price range simply do not have, so for that reason I think most people are going to be better served going for HD 6XX or a FiiO FT1 Pro in this price range.

Hopefully this is a teachable moment for Moondrop, because I do think the Horizon could’ve had potential, but what we got is just an exceedingly flawed headphone that I don’t think anyone will really enjoy any more than headphones at even 1/4th of Horizon’s price.