Moondrop In-Ear Monitors and Ear Buds

Reshelled B2s courtesy of itsfit labs. Very nicely done. Left piece kept sliding out a bit and was getting annoying so thought it was worth the gamble. Came out very nice and good fit too, first time!



The Moondrop Chu is an in-ear monitor (IEM) which uses a single dynamic driver. The Chu was provided to me by Shenzhen Audio in exchange for my evaluation. The Chu retails for $19.99.


The Moondrop Chu comes in a square black box that features Moondrop’s infamous waifu on the front face. Technical specifications for the Chu are provided on the rear of the slipcover in English and Chinese. A frequency response measurement is also pictured.

In addition to the IEMs, the package includes a black felt carry pouch with a snap closure. The Moondrop logo is printed on the pouch in white. The Chu also includes three pairs (S, M, L) of Moondrop’s Spring eartips. As has been pointed out by many observers, the Spring eartips by themselves retail for more than half the Chu’s list price. In terms of documentation, a manual, a contact card, and a quality control chit are included with the Chu. Of these, only the manual includes English text in addition to Chinese.


The Chu features all-metal construction. Contrary to what other reviewers have stated, the Chu does not have the same finish as the Aria. The Chu’s finish is smooth with a shiny luster, whereas the Aria’s finish was slightly textured and matte. The faceplates are oval-shaped and feature a copper fanned-leaf illustration that radiates forward along the X-axis. “L” and “R” indicators are also printed in copper adjacent to the cable entry sites. The nozzles have a lip to secure eartips, which is relatively novel for Moondrop IEMs and is greatly appreciated. The nozzles have saucer plate-style mesh coverings. There are two pinprick circular vents on the interior face of the IEM body.

The fixed cables are forward-swept and have hard rubber strain relief at the base. The cable is unbraided and uses a soft rubber sheath. The Y-split hardware is a hard rubber disk embossed with Moondrop logos on both sides. The L-shaped 3.5mm jack hardware is hard black rubber with substantial strain relief. There is no chin-adjustment choker and the cable is moderately tangle-prone. The cable does not have preformed earguides but the Chu comes with two optional soft plastic earguide attachments.


The Moondrop Chu is intended to be worn cable-up. The nozzles have a shallow insertion depth. Given the relatively small size of the earpieces, the Chu is very comfortable to wear for extended periods, but secureness of fit and isolation are slightly below average. The Chu has minor driver flex.


Measurements of the Moondrop Chu can be found on my expanding database:

Squiglink — IEM frequency response database by Bedrock Reviews

My measurements are conducted with a Dayton iMM-6 microphone using a vinyl tubing coupler and a calibrated USB sound interface. The measurements use a compensation file derived from relating my raw measurements to published measurements from Crinacle and Antdroid. There is a resonant peak around 8k. Measurements above 10 kHz are not reliable.


Moondrop Chu — Squiglink by Bedrock Reviews

The Moondrop Chu is tuned to the same Virtual Diffusion Sound Field target as many of Moondrop’s other IEMs. This is a Harman-ish sound that emphasizes sub-bass over mid-bass, features a robust pinna gain region centered around 3 kHz, and slopes downward from the pinna gain region through the upper treble.

The Chu’s sub-bass shelf is mild in its amplitude, just a hair north of neutral to my ears. Sub-bass extension is average. Bass articulation and resolution are very good. The bass is decently textured but is lacking in impact. While the level of restraint on display here is admirable, the Chu would have benefitted from a bit more bass quantity. The bass does not bleed into the lower mids.

The Chu’s midrange is on the cooler side and puts vocals front and center. Male and female vocals are roughly even with each other. Male vocals have body, warmth, and grit while still being very intelligible. Female vocals are vibrant without sounding oversaturated or breathy. Each budget single dynamic driver IEM Moondrop releases seems to strike a slightly better balance between vocals and midrange instrumentation. Where vocals once tended to disappear beneath male vocals on the now-venerable Starfield, the Chu’s midrange balances the two more successfully. There is a tasteful amount of presence that does not stray into sibilance. Timbre is very natural sounding.

The Chu’s treble is the most uneven element of its frequency response. It is front-loaded with lower treble energy. While not harsh, the lower-treble emphasis is followed by a noticeable drop-off in the mid-treble which deprives cymbal hits of sparkle. On the other hand, the Chu has a surprising amount of upper treble air for a product at this price point. While treble transient delivery is slightly smeared, the overall level of detail retrieval is excellent for $20. Instrument separation and imaging are also quite competent, and the soundstage is comparable to the Chu’s more expensive elder siblings.


The Moondrop Chu is harder to drive than many comparably priced IEMs and requires a quality source device. I did not notice any hiss during my listening on any of my source devices.


The Moondrop Chu is the best IEM $20 can buy. Every other IEM at this price point comes with at least one major tuning shortfall. The Chu does not.

The Moondrop Chu can be purchased here:

MOONDROP CHU Headphone Titanium IEMS Wired Dynamic Driver HiFi In-ear (


The Chu are my first Moondrop IEMs and They aren’t too bad but I am getting some sibilance on vocals and also on the spoken word when listening to Youtube. I’m finding the sound a touch thin, bass detail is good but lacks a bit of weight. Just when I feel I’m starting enjoy them I get , what I can only describe as, a metallic sounding sibilance on some of the treble. I’m hoping once I get more hours on them that may ease off.

I usually prefer foam tips but so many seem to going on about the moondrop tips I’ve left them in. Certainly when listening to music without vocals these are quite nice but I’m just getting a little too much sibilance at the moment.

You certainly get a lot of material value for £20 and they are quite comfortable. got to add they got from Shenzhen Audio to the UK in about 2 weeks which is very good and it may have been quicker if it wasn’t for the courier this side. I bought these as I was contemplating the Aria and thought for £20 this would be an easier gamble.

Current listening has been using the RME and Chord Mojo using mainly metal and indie based music. I’m going to give a few classical albums a go shortly. There’s certainly more positives than negatives. I also think I need to get a bit more accustomed to the Moondrop tuning. I’m still quite surprised at the amount of detail coming across for just £20.


Well after listening to these solidly for a few days now I have to say I’m giving up on them. They may have nice detail through the midband but I can’t control that sibilance that appears on too many vocals, even finally retipping them with some foam tips. The foam tips add a bit of bass but that treble is still too harsh and splashy for my liking.

Listening to symphonic music when crescendos kick in or it gets very busy it becomes a little messy and harsh. Listening to some Lou Donaldson the hi-hats all too often sound splashy and double bass lacks the presence and weight it should have. I was hoping retipping would help control that treble but it hasn’t, it remains messy and it may be extended but with that lack of bass weight just makes things sound too thin and harsh for me.

At this price point I far prefer the CCA CRA. After all I’ve read about the Moondrop DD IEMs and similar sounding signatures I’m glad I took the plunge at this price rather than their more expensive IEMs. These, sadly aren’t for me. I still want a more expensive pair of IEMS to go along with my ER2XR, although something not quite as invasive, the search will continue elsewhere.


China oh China,

when will this low-wage country finally get a grip on its quality controls?


Maybe if they pay higher wages?



Moondrop Chu

The Moondrop Chu have been sent to me by HifiGo in exchange for my review. The only request has been the usual inclusion of (non-affiliate) links to the product via there store, which you can find by visiting the version published on my blog. Therefore, my review will aim to be as honest and free of bias as possible, although you should always consider the fact that it hasn’t cost me anything.


It has been a while since I last posted a review of a sub 50€, a price range that I have always liked to focus on here. The Moondrop Chu is not only less than 50€, it is less than half of that, coming in at around 20€.

I have always been a bit of a Moondrop fan, enjoying most of their IEMs and still using the Aria as my main bluetooth IEMs (connected to an MW200), therefore I am always happy to try out new models from them and if they are models that come in this cheap, even more so.

If any of you follow the budget IEM sector, you may have already seen the Chu get quite a bit of praise, at least from the majority of users, so let’s see if they get more praise (or not) from myself.


This is a set of 20€ IEMs, therefore anything more than the IEMs, a cheap cable and a couple of silicone tips is probably already a bonus.

In the case of the Chu, the cable is fixed, which is a let down for many but it needn’t always be a bad thing (more on that in a second). We also get, as expected, 3 sets of silicone tips. However, the tips included are not normal generic cheap silicone that end up in a big box of tips (in my case at least), they are Moondrop Spring tips which actually cost over 12€ for a set of three sizes like the ones included.

We also get a small felt pouch for storage, which while not exactly a high class case, it still does its job and keeps them free of dust, dirt and scratches while not in use. Finally, apart from the usual documentation, we get a set of rubber ear hooks (which I will discuss with the cable in a moment) and a wooden decoration piece which has the anime girl engraved on it (I have no idea what this is to be used for, but anyways, it is included).

All of this is presented in a simple black box with a transparent cover that shows the same anime girl and the IEMs sitting in their respective cut outs.

Build and aesthetics…

Starting with the IEMs, they are not the usual shape commonly found on IEMs, nor are they the small button type found on things like the Quarks, they are sort of in between. The shape is actually just a small oval that the (fixed) cable comes out of near the top front, angling slightly downwards. The decoration is black with a gold leaf type symbol (well, it looks like a leaf when the IEMs are held upside down), which is not exactly stunning but doesn’t look too bad. The IEM shells are metal and look as though they are well assembled, although only time will tell in this regard (Moondrop don’t always have the best rep for paint durability).

The cable, as I said, is fixed and I said that this is not always a bad idea. The thing with fixed cables is that it stops worries about which cable to buy, will I notice an upgrade, etc. Here, you get what you are given, for better or for worse. In the case of the Chu, the cable is not actually bad, especially if we consider the price point. It is a simple rubber coated not braided cable, it’s not microphonic, it’s not a bad length and, well, it just works. As with most people, I do prefer a detachable cable but at least this cable is decent enough to not hate it.

Finally the tips, I think they are great. I hadn’t actually tried these tips before (I’m not sure how long they have been available) and was genuinely impressed when I used them on the Chu. I also tried them on the S12 (as I mentioned in my S12 review) and found them to be great, enough for them to be my tips of choice for those IEMs.

With the Chu, I find that I use a medium set (they seem to be slightly smaller than other brand tips) as I get a seal quite deep inside my ear (due to the shape and size of the Chu), while on the S12, the large set works better for me. Another win as 1 set of tips has served 2 IEMs. Many times I only end up using one, or none, of the included tips and the others end up lost in a big box of tips somewhere.

Before wrapping up this section, I just want to mention fit and comfort. There are rubber ear hooks included with the Chu, something that I very rarely use as I prefer not to have the preformed hook over my ears. However, in the case of the Chu, I found that the cable had the habit of springing off my ears so I gave the hooks a try and they work very well. The cable does pop out of the hook sometimes when removing them but that is a minor gripe and overall I must say that I find the Moondrop Chu to be very comfortable in my ears. The deepish fit allows me to lay on my side (something that I usually use the Quarks for but will probably replace them with the Chu) and the tips are just very comfortable.


That was quite a lengthy build and aesthetics section for a set of 20€ IEMs, so lets get on with the most important part, the sound.

In the subbass there is quite an impressive extension. It is not the most rumble you are going to find in a set of IEMs but it has enough to do it’s job and present those low notes with enough authority to find them enjoyable. In comparison to the Quarks, I find the subbass to be easier to appreciate, even though measurements show that it is not really that different down in those regions, but it is the midbass that makes it seem more likeable (to me).

The thing that I like about the midbass is the fact that there is no midbass bump like there is on the Quarks, or on many other budget models (all the ones I have tried) from the brand. In fact, I think the Chu is the closest tuning to my preference target that I have heard from them. The lower end is actually tuned similar to the Dusk, although at a slightly reduced level of presence.

Here is a graph of the Chu compared to my personal preference target:

(all of my measurements can be found and compared on

This obviously puts the Chu off to a good start as far as its tuning in the lower ranges, giving me the impression of being clean and well balanced.

Taking some songs from my test track list, things like “Long After You’re Gone” are presented very well in the mid bass range, or “No Sanctuary Here”, which is more midbass focused, has plenty of clean and articulate bass, without giving the feeling that it is lacking (at least to me).

There are obviously some tracks that can benefit from a little bit more of a midbass presence than found on the Chu, such as “Jack Of Speed”, but I found that the Gryphon (or Go Blu) gave me that little bit extra when needed and that the Chu take it quite well.

Moving into the mids, they are well balanced and I have no complaints throughout the whole range. Vocals are present, instruments are easily separated and in general they do a pretty good job for a set of 20€ IEMs.

My first, and possibly only major, complaint comes when we hit the 5kHz mark. AS I have said plenty of times in the past, I seem to have a bit of sensitivity to 5kHz peaks and that is where the main peak in the upper ranges is on the Moondrop Chu. This can make certain instruments come across to me as harsh. There are certain upper guitar notes, percussion hits, and other things that just have too much presence in that region and can make me wince a little, depending on the track.

This is something that I think affects me more than others, as everyone’s a little more sensitive to different things, so it probably won’t even be an issue for most people, but for me it does detract a little from the enjoyability of these IEMs, especially over longer listening sessions as I can find them tiring.

The upper treble has a decent extension to it, with a nice sensation of air and I really can’t complain much about these higher ranges. It is not the smoothest of treble’s but it is acceptable, especially if we go back to considering the price.

Details are not the greatest but are acceptable. Background details can be a little hazy, seeming to be a little out of focus at times, but again, we are talking about a set of IEMs at 20€, at this price I feel they are adequate, although not amazing.

Soundstage is about on a par for a set of IEMs in this realm, with enough space and enough imaging to appreciate things like binaural recordings, but don’t expect a huge space outside your head.


The Moondrop Chu are a very good set of IEMs for their price. As far as sound, my only real complaint is that 5kHz peak that I mentioned, but as I also said, this probably affects me much more than it does other people. Other than that, I find that the sound is very good for the price bracket that these sit in.

In fact, on a sound level, these could easily be placed much higher, although I think that things like detachable cables would start to be a little more important if we start scaling the price ranges.

The contents included are also satisfactory for the price, except for the tips, which are worth the purchase almost by themselves. Maybe this is actually a good marketing move by Moondrop, they have a set of cheap IEMs with good sound that is receiving praise and will get many people to try them who may not have considered Moondrop in the past. At the same time, they include a set of tips that they sell separately for more than half the price of these IEMs, which are very good tips (in my opinion) and this may increase the sales of those tips by quite a bit also.

Whichever way we look at it, there is no way I can say that the Moondrop Chu are not worth their price, they are more than worthy. At a price of 20€, I don’t see them as anything other than a win.

As always, this review is also available in Spanish both on and on


Thought I’d share a tiny tidbit of experience with the Blessing 2 Dusk and the Variations. Now that I’m starting to go into work, I decided to get some daily drivers for when I’m there.

My headphone listening has been pretty much all desktop for the past 2 years, with Bifrost 2 > Phonitor XE > VC / RAD-0. And I got… used to that. Both these headphones have a really pleasant and neutral tuning, with superb detail, bass, and slam. And I didn’t want to give up too much of this experience when stepping down to IEMs.

So with my $500 budget and after reading reviews, I narrowed it to one of the B2D and Variations. Plan was to buy both and sell / return the other.

I got and tried the B2D first, and I can tell why they’re highly recommended. But while the B2D’s are GREAT for their price point, their warmth and general resolution made a lot of tracks “blend”. In a good way, mind you, since the end product was really cohesive. But I could tell a pretty clear difference in detail. And I couldn’t get used to it.

For example, Chocolate Chip Trip by TOOL is one of my favorites, with different instruments sounds moving all around you at the same time. It sounded fine on the B2D, but I had a hard time picking out all sounds all at once like I can with the desktop setup. It lacked breathing room, somehow.

The Variations has been a much better transition in that vein, and I’ll likely end up keeping these. They are much more neutral w/ a sub-bass bump, and a bit more resolving than the B2D. The tonality also lends itself well to a more spacious presentation of the music, which is a good transition from the current desktop drivers.

Super cheap “review”, but if you’re a detail + subbass head on the lookout for non-kilobuck IEMs, I highly recommend the Variations.