Marcelo reviews the MOONDROP Harmon, an XTM Series triple 10mm dynamic driver universal in-ear monitor with a VDSF-based tuning. It is currently priced at $349.99.
Disclaimer: This sample was sent to me in exchange for my honest opinion. Headfonics is an independent website with no affiliate links or status. I thank MOONDROP and Shenzhen Audio for their support.
Click here to read more about MOONDROP products we have previously reviewed on Headfonics.
This article follows our current scoring guidelines, which you can read here in more detail.
The triple-dynamic driver MOONDROP Harmon in-ear monitor may not have the technical performance as its primary attribute, but the sound signature and tonality more than compensate for that.
It may not wow you with the most pinpoint imaging or a stadium-like sound staging, but what you have instead is a warmth that fills your soul, or at least your musical hunger.
I’ve always put Moondrop in high regard when it comes to in-ear monitors, due to their innovations, and have bought some of their products, some of which have been reviewed here at Headfonics, such as the Blessing 3, May, Dawn Pro, and the MoonRiver 2 dongle DAC.
What they have in common is the excellent tuning that I like. They mostly focused on excellent vocal reproduction, with forward treble and neutral bass. That made Moondrop popular. But they turned over a new leaf with the Moondrop Harmon IEM.
The new tuning style of the $349 Moondrop Harmon is quite a surprise for me. This was an unexpected departure from their usual house sound or tuning style.
So, how does the Moondrop Harmon sound? Or more importantly, how does it differ from their previous tuning style with the Blessing 3? Come with me and let’s dive into this journey together in my review below.
Design & Features
Moondrop Harmon features some compelling innovations. Firstly, the 3 10mm dynamic drivers per channel in a small IEM shell, which is unheard of at this price range.
One driver is a 10mm Dynamic Driver with Glass Dome Composite Diaphragm for midrange and high.
The other two drivers are Dual 10mm Paper Cone Composite Diaphragm Bass Dynamic Drivers configured in what they call Horizontally Opposed Dual Dynamic Driver System, or H.O.D.D.D.U.S., which is also featured in my Blessing 3.
Using a glass dome composite diaphragm driver is an excellent innovation that gives the Harmon its beautiful sound.
Its sensitivity rating of 14dB/Vrms @1kHz, and impedance of 19Ω are, on paper, average, but in actual use, tell a different story, which will be discussed further in the review below.
Another reason to believe Moondrop has turned a new leaf is the use of a non-flashy minimalist design.
It looks like an industrial Bauhaus, with its randomly faceted faceplate and the shell form that follows function, dictated by the position of the drivers aligned in tandem.
Comfort & Isolation
Due to its lightweight, small size, and ergonomic shape, it is very comfortable to wear. It never caused me any discomfort during long listening sessions.
The seal of the ear tips is excellent; it is easy to seal when putting the IEMs in the ears, and it stays sealed during my walking exercise. It has a good grip and doesn’t need constant adjustment in the ear.
It has a pressure release system, preventing pressure build-up in the ear canal, which makes listening uncomfortable, but walking nauseating due to the constant change in pressure with the movement of my head.
The isolation is average, which isn’t bad for casual use, especially outdoors, as you need to hear some sound from outside, for safety.
Stock Cable
It’s nice that Moondrop didn’t become stingy this time, unlike what they did with the thin cable on the Blessing 3. The Harmon stock cable is excellent; it is thick, soft, and not too heavy, perfect for portable use.
I like the small-sized modular plug. It is as small as non-modular ones, so you wouldn’t know unless you look closer.
Packaging & Accessories
A black box with a white sleeve and a drawing of a girl completes the exterior look.
The packaging is simple in design; once you open the box, you’ll be greeted with the IEMs on display and a beautiful black fake leather carrying case. It includes the manual, three pairs of ear tips, and a thick modular cable with 4.4mm and 3.5mm plugs.
Sound Impressions
I have observed that the Moondrop Harmon is very sensitive to sources, so I used three sources with different sound signatures: the Muse HiFi M5 Ultra DAC/ amplifier, the Shanling M3 Plus digital audio player, or DAP, and the iBasso DC-Elite dongle DAC.
When switching between sources, the difference in sound is immediately noticeable, which will be discussed further in the pairing section on page 2.
I used the UAPP music player app for this review, without any EQ or sound enhancement.
The stock cable’s 4.4mm balanced connection was used to maximize the power from the sources. I also use 4.4mm balanced cable for the other IEMs in this review for equality.
At least 24 hours of burn-in were completed before serious listening to ensure the drivers have settled. In hindsight, 12 hours for the Harmon is enough, as it does not need a long burn-in period.
Summary
I was expecting the usual Moondrop sound, with the bass neutral, the upper midrange forward, and the treble on the bright side.
I’m not implying anything wrong with that tuning, but I was pleasantly surprised with the bassy, warm tonality of the Moondrop Harmon.
It was delightful to hear that it has a bassy-warm U-shaped sound signature and an energetic sound presentation.
Bass
It may not be considered a bass-head IEM because the measured graph shows only 10 dB of boost, which is about 6dB more boosted than neutral, but for a Moondrop IEM, it is unusually bassy.
This is the most exciting part of this IEM; the bass arrives in a weighty, thickly textured, dynamically expressive, and fast manner. Resulting in a punchy but articulate sound.
Using two 10mm bass drivers allows it to be unusually dynamic. With the input signal shared by two voice coils and the combined surface area of two diaphragms, it can take more power with less likelihood of power compression under loud volumes, giving it an excellent dynamic range.
It sounds polite and relaxed when not needed, especially in some genres like old pop music or country music, it is robust and has a huge presence, especially in rap songs and most electronic music I often listen to, like synthwave, chillwave, and such.
Overall, their Horizontally Opposed Dual Dynamic Driver System or H.O.D.D.D.U.S. may sound like a gimmick at first, but it is not, with its implementation and tuning to the Harmon, and based on what I’m hearing, it provides a real improvement in the bass over a single driver.
Midrange
It has a smooth, clean, warm, and laid-back midrange, not shouty, harsh, and aggressive; Moondrop’s innovative use of a glass dome composite diaphragm driver for the mid-high must be responsible for its low distortion.
The lower midrange has a nice warmth that makes the instrument decay, lush, and prevents its note weight from sounding thin and cold.
The male vocals are accurately presented with the correct chestiness and fullness, with only a hint of recession in presentation.
There is a little forwardness in the upper midrange, but not too much to call attention. It renders the female vocals nicely with good immediacy, intimacy, and palpability, yet never shouty and harsh.
It is elevated enough to counter the bass boost, preventing the whole musical presentation from sounding muddy, but not too much to dominate and color the sound.
Treble
It is very extended, clean, and airy with a laid-back and gentle presentation, which I attribute to its use of a glass dome composite diaphragm driver.
It sounds different yet correct from other dynamic drivers using different and more familiar materials; it doesn’t seem to have audible diaphragm break-up modes in the upper treble to make the sound congested. It has a clear treble sound.
There is an absence of harshness to the treble, letting the micro details be heard clearly, but the presentation is laid back and polite, making the details not the focus of its sound, but only adding richness to the music.
I’m not complaining, but I would have loved it more if the upper treble were more forward to suit my taste better. As it is now, it is fine, and I speculate that many people will like it.
Staging & Imaging
Most bassy and warm-tuned IEMs don’t have technical performance as their prime attribute, and the Moondrop Harmon is no exception.
It has an average-sized spherical soundstage, meaning it is equally deep, wide, and high. And because of the spherical soundstage, it feels natural, even though it is not the biggest, it feels like you are in a small jazz club.
It’s not the best or the most defined, but the images it produces are certainly above average; the vocals may not be the most defined, but they hover in front of you with excellent stability. The instruments surrounding the vocals occupy their own spaces and are presented laid-back.
There’s a nice amount of front-to-back layering of the images, and again, it’s not the best, but certainly above average.
The difference between the softest and the loudest is excellent, especially in the bass, due to the use of two 10mm bass drivers.
Not having the best technical performance is not a bad thing. Sometimes, technical performance takes away from the raw enjoyment of music and pushes you to an analytical type of listening, which isn’t the right way to enjoy music.
Click on page 2 below for my pairing recommendations and selected comparisons.
