Sonic Compass · Mojo Review · IEM (universal) · Session Review
Cozoy D1
A US$30 single dynamic driver IEM with a bright V-shaped, Harman-leaning tuning: tight mid-bass punch, a lively top end with good separation, and a flatter, left-to-right stage.
A lively, bright V-shaped IEM with tight punchy mid-bass, a detailed crisp top end and a flat but well separated stage, in a good-looking shell with a better cable than the price suggests.
- Bright, lively V-shape
- Tight, punchy mid-bass
- Crisp, detailed treble
- Easy to drive (32 ohm, 100 dB)
- Good-looking shells and a better cable than the price suggests
Where it sits
Sonic Compass does not score gear out of ten. Gear and listeners are plotted on the same seven axes, so a review tells you where a product sits — and you can see how far that is from where you sit. A position is a description, not a grade.
- Tone ColourCool · 35%
- Texture DetailDetailed · 75%
- Dynamics JumpPunchy · 72%
- Space & ImagingBalanced · 58%
- Timing & FlowBalanced · 55%
- Comfort & FatigueEasy-going · 62%
- Emotional EngagementImmersive · 70%
Bright V-shape following the 2019 Harman target, with a slight mid scoop and crisp treble. The Chorus is warmer. (Low = bright on this scale.)
Excellent resolution and detail up top, gentle crispness, natural guitar and vocal timbre with no plasticky or metallic sheen. Detail was very similar to the Chorus.
Tight, punchy mid-bass that slams when turned up, with sub-bass present. A better cable added more dynamics and weight.
Reasonably wide and easy to pinpoint, with good instrument separation, but flat and left to right, with little depth and nothing holographic.
Placed near the middle with thin evidence. He says busy tracks like Metallica's One get congested deep into the track, as most gear does, and he gave no direct timing remark.
Lightweight, compact shells that fit most ears. Treble can border on sharp or sibilant on hot tracks for some listeners, and the 4 to 5 kHz region gets shouty at high volume. He did not find it a problem.
Lively, energetic and exciting, with powerful female pop vocals and strong enjoyment on banjo-heavy metal.
Sonic Compass does not grade gear. We plot gear and listeners on the same seven axes, so a review tells you where a product sits and you can see how far that is from where you sit.
The Cozoy D1 is the first model from a brand founded in 2025, a single 10mm dynamic driver IEM in the roughly US$30 budget class, where Tangzu, Simgot and 7Hz are the usual names. Cozoy sent the pair for review with no expectations or influence. I listened through my DAP using the stock cable and the stock silicone tips.
Listening journey
Bass — Tight, punchy mid-bass that does not bleed into the lower mids, with some sub-bass rumble when the track asks for it. Electronic kicks hit low and clean, and with the volume up they really slam. On metal and rock the bass tames slightly: it is not the star but it is not forgotten.
Mids — I assume there is a slight scoop. They are not shouty, forward or harsh, which suits me as an unashamed V-shape fan. Guitar and vocal timbre are natural, without a plasticky or metallic sheen. Female vocals have great presence. If you push the volume, the 4 to 5 kHz region can get a fraction shouty, so I keep it moderate, where the D1 sounds nicely transparent.
Treble — Excellent resolution and detail with a gentle crispness, and good separation on acoustic strings and cymbals. On hot, busy rock and metal it can border on sharp or sibilant for some listeners. It was not a problem for me, as I can handle plenty of treble.
Stage and imaging — Not class leading, and it should not be at this price. The airy treble helps imaging, and placement is easy to pinpoint. The stage is reasonably wide but flat: more left to right than 3D or holographic, with little depth behind me. On a busy banjo and guitar track, guitars separate nicely from the banjos and the drums sit apart from both.
Tips — A pair of foam tips is included. I did not like them as a rule and stayed with silicone, but they are there if you want to take a fraction off the treble brightness and fill out the stage a little.
| Track | Position | Note |
|---|---|---|
| The Ghost | 88% | Banjo sounds fantastic; low end gains presence with the better cable |
| One | 70% | Cymbals and guitars a little sharp at the start, congested deep into the track |
Critical observations
Where the D1 sits — An old-school, brightish V-shape that follows the 2019 Harman target closely. Lively and energetic, with the focus on mid-bass punch and a crisp, detailed top end.
Build and fit — Medical-grade 3D-printed resin shells with a pitch black inner cavity and a deep ink blue faceplate that shifts towards purple in the light. They are lightweight and compact and fit most ears easily. The metal tuning nozzle is a durability upgrade at this price. The cable is a four-core silver-plated single crystal copper cable in a pearlescent purple jacket, 0.78mm two-pin to 3.5mm, much better than the usual cable at this price. Left and right are marked in red and blue on the IEMs and the cable.
Driver — The maker lists a 10mm dual-magnet, dual-cavity dynamic driver with a graphene diaphragm, 32 ohms and 100 dB sensitivity. It is easy to drive, and many phones and dongles can power it without a desktop setup.
Cable swap — I tried a roughly US$60 aftermarket braided cable with a 4.4mm balanced termination. It is louder at the same setting because it uses the balanced output, but once matched it brought more dynamics, body and weight, and more presence in the bass and sub-bass. The stock cable does not lack body, but the better cable was bringing more. On my DAP I preferred the upgrade cable on medium gain, where it sounded smoother and more cohesive, and the stock cable on high gain.
Against the Kiwi Ears x B_Media Chorus (about US$40, single DLC dynamic driver) — Both punch well above their price and sound fantastic from my DAP. The D1 is a little more energetic and exciting, especially up top, with a crisper treble and a more vibrant female vocal. The Chorus is a little smoother and warmer, with fuller bass that goes a little deeper, and richer, fuller male vocals. Resolution and detail were very similar. The D1 reads as a V-shape and the Chorus as more of a W-shape. Staging and imaging are very similar, flat and left to right, and I would give imaging to the D1 by a hair, though some tracks made me think the Chorus images well too.
Honest limits — The pair was supplied by the maker. By ear only, with no measurements, from one DAP, mostly with the stock cable and silicone tips. I did not use the foam tips. The comparison with the Chorus was made while I was reviewing it, and the Chorus is priced a little higher.
- The GhostFraser Edwards
- Poseidon's RageFraser Edwards
- OneMetallica
- Knights of CydoniaMuse
- Out of My MindAva Max
- Welcome to the Black ParadeMy Chemical Romance
- AvalonRoxy Music
- StrandedHeart
- Driver Configuration
- Single 10mm dynamic driver, dual magnetic circuit, dual cavity, graphene diaphragm (Cozoy)
- Driver Details
- Impedance 32 ohms, sensitivity 100 dB, frequency response 20Hz to 20kHz (Cozoy distributor listing)
- Weight
- Not stated on the maker page
- Build Materials
- Medical-grade 3D-printed resin shell, metal tuning nozzle
- Cable Connectors
- Detachable 0.78mm two-pin; cable about 1.2m, silver-plated copper, 3.5mm single-ended plug. A version with microphone is also sold.
- Isolation Leakage
- Not measured
- Power Requirements
- Easy to drive from a phone or dongle
- Accessories
- Cable and ear tips in several sizes, including foam and silicone (the exact count varies by listing)
- Build Quality Notes
- Price: US$30 without microphone, US$31 with microphone (Cozoy store). Photos: Cozoy.
A lively, bright V-shaped IEM with tight punchy mid-bass, a detailed crisp top end and a flat but well separated stage, in a good-looking shell with a better cable than the price suggests.
<p><strong>Buy it if</strong>… you like a brightish V-shape with punch and sparkle; you listen to pop, EDM, electronic, rock or metal and want female vocals with energy; or you want an easy-to-drive budget IEM that also suits a first purchase.</p><p><strong>Skip it if</strong>… you are sensitive to treble that can turn sharp on busy tracks; you want a warmer, fuller bass and richer male vocals (the Chorus leans that way); or you want a deep, holographic stage.</p>