This $20 wired earphone plays music with surprising naturalness and refinement!
When you talk about IEMs nowadays, you have to talk about Moondrop. They know how to crank out reasonably priced earphones with impeccable tonal balance, and the headphone enthusiasts are eating them up.
Today we have their latest IEM, the $20 CHU Dynamic Driver IEM which provides an eye-catching metal housing with a large dynamic driver and Moondrop’s popular Harmon Target-based tuning. With the CHU, they promise a budget earphone with exceptional clarity and a sound that complements many genres, so I’m itching to see what they can provide for such a meager outlay. Read on, and I’ll let you know what I think!
Disclaimer: The review unit I have on hand is provided by Hifigo. No input has been given regarding the content contained in this evaluation.
To start with, I think the CHU is exceptionally well made for a $20 earphone. The painted zinc alloy housings have a nice weight, and the finish is nice and smooth with no rough edges. They seem pretty durable, exceeding my expectations for the price point.
The cable isn’t detachable, and it’s a little stiff, but it’s acceptable for twenty bucks. You can get a version with an inline mic for a little more cash, which is pretty cool if you plan to use it as a headset.
Also, keep in mind that the cables on the CHU are meant to be worn over the ear, but there is no built-in memory portion to help secure them. The package includes rubber hooks to help guide the cables over the ear. I personally draped the bare wire over my ears which was sufficient for the most part.
A single 10mm titanium-coated dynamic driver is inside each metal housing with a high-sensitivity magnet and voice coil structure. This allows for paring with various sources, including smartphones and tablets.
With its angled oval design, the Chu’s earpieces fit my ears like a glove, making them comfortable and secure. The included “Spring” ear tips were also super soft, providing additional comfort for long listening sessions.
Speaking of the Spring tips, they’re also internally ribbed to smooth out the high-frequency response. In addition, the ribs provide the rigidity needed to firm up the bass response. I have to say; it’s nice to see such high-quality ear tips included with such inexpensive earphones.
In the box, you get three pairs of Spring tips (S,M,L), a snap storage pouch, two rubber hooks to secure wires when wearing, along with warranty/instruction paperwork.
- Sensitivity: 120dB/Vrms(@1KHz)
- Impedance: 28 Ω 土15% (@1khz)
- THD: THD@1KHz≤1%
- Frequency range: 10Hz 35kHz (IEC61094, Free Field)
- Effective frequency response: 20Hz -20kHz (IEC60318-4, -3dB)
Moondrop has gone with its popular VDSF target response curve when it comes to tuning. This isn’t surprising since this is basically the “secret sauce” behind its earphones. At the end of the day, VDSF is a slight tweak of the “Harmon Target Curve,” a frequency response curve held up to represent the sound that is pleasing to the majority of ears.
With VDSF, Moondrop adds a little emphasis to the sub-bass and presence (upper-mid) regions of the Harmon Curve, which adds openness, crispness, and weight to the sound. Hifiman has used a similar approach on some of my favorite headphones, like the Sundara and Edition XS.
For my sound tests, I connected the Moondrop CHU to my Fiio M11 Plus digital audio player and played a wide variety of test tracks from Tidal. As expected, I found the CHU to have a balanced and open presentation, with a decent soundstage. Center mids and bass were very clean and extended, as were the upper mids and treble. Tuning was pretty masterful for the price point.
The only thing that may bother some about the tonal balance would be a slight lack of punch in the mid-bass, but this was a plus for someone like me who likes tight, deep bass.
I wouldn’t call them the most resolving earphone I’ve ever heard, but resolution and detail were remarkable for a sub-20 dollar earphone. Listening to “When a Woman Loves a Man” from Tigran Hamasyan, I thought the cymbals and piano had a really lovely texture, even if the overall detail was soft.
Conversely, I did find songs that featured horns or high female vocals to be just a touch edgy due to the slight upper-mid bump, but not overly so. Most of the time, I enjoyed the openness provided by the added presence.
Listening to “Still” by Seinabo Sey, the wide staging and separation enraptured me. The lead vocal was nicely delineated from the background vocal and instrumentation. The way the Chu imaged would be good at any price.
If I had any real complaint about the Chu, it would be with dynamics. Bass dynamics were just a little subdued, which kept electronic tracks like deadmau5’s “Strobe” from really hitting as they should. However, for someone like me who isn’t a real basshead, they played with sufficient microdynamics and speed to play it satisfactorily.
They sounded pretty good with any genre, but they excelled when listening to acoustic music, like blues, folk, jazz, etc.
For kicks, I put them up against another budget earphone I like, the $79 TinHiFi T3 Plus, and even though it cost about $60 less, the CHU held its own.
The TinHiFi T3 Plus was superior in most metrics, like more even response thru the upper mids, more detail, more separation, and better bass dynamics. That said, the Chu gave me about 75% of what I got from the T3 Plus in most of these aspects, which shows how accomplished it is for a $20 IEM.
The Wrap Up
If you’re looking for a balanced-sounding IEM and don’t have a lot of cash to spend, the Moondrop CHU is a no-brainer. It’s comfortable, well-built, and has clarity and soundstage beyond what is expected at this price point. The only knocks I see are a slight lack of punch for the bass heads and a non-detachable cable that could fail down the line.
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I’m an audio writer who started as a young audio salesman/consumer electronics professional back in the late 90s. That’s where I discovered the magic of 2-Channel sound. My hunger for great sound has led me on a delightful music quest that continues today.