I’ve been spending the last few weeks swapping between two of the most hyped sub-$25 in-ear monitors on the market: the Moondrop Chu II DSP and the 7Hz Salnotes Zero 2.
Both IEMs follow up on legendary predecessors that completely reshaped the ultra-budget audiophile space. However, they approach the budget formula from two very different angles:
- Moondrop Chu II DSP ($22–$25) comes with an all-metal build, swappable brass nozzles, and a direct USB Type-C DSP cable with built-in DAC and customizable EQ.
- 7Hz Salnotes Zero 2 ($20–$24) is the Crinacle-tuned sequel featuring a lightweight polycarbonate shell, classic 3.5mm analogue connection, and a noticeably warmer, bass-boosted sound signature.
If you are torn between the plug-and-play digital versatility of the Chu II DSP and the analogue warmth of the Zero 2, here is my hands-on breakdown across design, real-world comfort, sound quality, gaming performance, and overall value.
Specs Comparison: Moondrop Chu II DSP vs 7Hz Salnotes Zero 2
| Specification | Moondrop Chu II DSP | 7Hz Salnotes Zero 2 |
| Driver Configuration | 10mm High-Performance Dynamic Driver (Al-Mg Alloy Dome) | 10mm High-Performance Dynamic Driver (PU+Metal Composite) |
| Connection Type | USB Type-C (Integrated DSP DAC Chip) | 3.5mm Gold-Plated Analog Jack |
| Cable / Connector | 0.78mm 2-Pin Detachable (with Inline Mic) | 0.78mm 2-Pin Detachable (OFC Cable) |
| Shell Material | Cast Zinc-Alloy with Removable Brass Nozzle | Polycarbonate Plastic with Metal Faceplate |
| App / EQ Support | Yes (Moondrop Link App with PEQ & Presets) | No (Purely Analog / Hardware Dependant) |
| Frequency Response | 15Hz – 38kHz | 10Hz – 20kHz |
| Impedance / Sensitivity | Driven by onboard DSP / 119dB/Vrms | 32Ω / 108dB/Vrms |
| Included Accessories | 3 Pairs Silicone Tips, Soft Leather Storage Pouch | 5–6 Pairs Colorful Silicone Tips |
| Price Range | ~$23 – $25 | ~$20 – $24 |
My Take: On paper, the Chu II DSP offers massive practical value if your smartphone lacks a 3.5mm headphone jack. The integrated Type-C DSP cable eliminates the need to carry an external DAC dongle (such as an Apple dongle or CX-Pro) while unlocking app-based EQ. The Zero 2, meanwhile, remains the traditionalist’s choice for dedicated 3.5mm audio setups and external desktop DAC/Amps.
Also Checkout: 7 Best Budget IEMs From ₹1,000 to ₹4,500 in 2026
Design & Build Quality
Holding both in your hands reveals an immediate contrast in design philosophy.
Moondrop Chu II DSP
The Chu II DSP features a matte-black cast zinc-alloy shell. It feels dense, premium, and surprisingly high-end for a $24 pair of earphones.
One of the best design upgrades Moondrop made here is the removable, unscrewable brass nozzle. In humid climates, condensation often clogs the acoustic mesh filters of metal IEMs, causing a drop in volume on one side. With the Chu II DSP, you can simply unscrew the brass nozzle to clean or swap out the acoustic filter mesh, dramatically extending the IEM’s lifespan.
The cable is a lightweight, soft-braided black wire terminating in an aluminium Type-C housing that hides the DSP/DAC chip and an inline microphone.
7Hz Salnotes Zero 2
The Zero 2 retains 7Hz’s signature geometric, angular look with sharp outer lines and a brushed metallic faceplate. The inner body is made of lightweight translucent polycarbonate.
While it looks eye-catching (especially in vibrant colour options like blue, orange, or black), the in-hand feel is unmistakably plastic compared to the Chu II’s cold metal.
The stock cable on the Zero 2 is a 4-core oxygen-free copper wire in a distinct brownish hue. It works fine, but it tends to be slightly stiffer and more prone to tangling than the Chu II’s cable.
[ BUILD HIGHLIGHTS ]
Chu II DSP ───> CNC Zinc Alloy Shell + Unscrewable Brass Nozzle + Carry Pouch
Zero 2 ───> Polycarbonate Shell + Metal Faceplate + Colorful Tip Options
My Take: The Moondrop Chu II DSP wins the build quality round hands down. The full-metal housing feels substantially more durable, and the unscrewable brass nozzle completely solves the long-term humidity and filter-clogging issues that plagued budget IEMs in the past.
Comfort & Fit
Even the best-sounding IEM is useless if it hurts your ears after 45 minutes.
Moondrop Chu II DSP: The shell is tiny and organically contoured. Because the inner body is smooth and free of sharp edges, it slides flush into almost any ear size. During my 3- to 4-hour continuous listening sessions, I experienced no outer-ear fatigue or pressure hotspots.
7Hz Salnotes Zero 2: The Zero 2 is noticeably larger and more angular. The squarish inner housing corners rest against the concha of your ear. If you have medium-to-large ears, it fits securely; however, users with smaller ears may experience slight soreness along the ear cartilage after extended sessions.
My Take: If you have small-to-medium ears or prefer sleeping/lying down with earphones, the Chu II DSP is noticeably more comfortable. The Zero 2 is by no means uncomfortable, but its bulky, angular geometry makes its presence felt much more than that of the Chu II.
Sound Quality
To test both IEMs, I ran them through a diverse rotation of tracks (rock, hip-hop, EDM, acoustic, and vocal-centric) and through extensive gaming sessions.
[ SOUND SIGNATURE OVERVIEW ]
Moondrop Chu II DSP: Tight Sub-Bass ─── Clean Midrange ─── Sparkly / Detailed Treble
7Hz Zero 2: Thick Mid-Bass ─── Warm Vocals ─── Smooth / Relaxed Treble
Bass (Sub-Bass vs Mid-Bass)
7Hz Zero 2: Tuned in collaboration with Crinacle, the Zero 2 introduces a warm, meaty bass response. Mid-bass instruments like kick drums, bass guitars, and acoustic tabla have a rich, physical thump. It sounds authoritative, organic, and forgiving on poorly mastered tracks.
Moondrop Chu II DSP: The bass on the Chu II DSP is faster, tighter, and focused more on the sub-bass rumble rather than thick mid-bass. In electronic music and synthetic bass drops, the Chu II DSP provides better texture and speed, without bleeding into the lower vocal range.
Midrange & Vocals
7Hz Zero 2: The lower midrange on the Zero 2 has body and warmth. Male vocals (e.g., deep acoustic ballads) sound lush and natural. Instruments carry an organic weight, making it a fatigue-free listen.
Moondrop Chu II DSP: The Chu II DSP prioritizes upper-midrange clarity and presence. Female vocals, acoustic string plucks, and brass instruments sound crisper and more forward. If you prefer high vocal articulation where singers cut cleanly through the mix, the Chu II stands out.
Treble & High-Frequency Detail
7Hz Zero 2: The treble on the Zero 2 is deliberately tuned for smoothness and non-fatiguing response. Cymbals and high-hats are present but rolled off just enough to eliminate sibilance (the harsh “s” and “sh” sounds). However, micro-detail enthusiasts might find it slightly dull at lower volumes.
Moondrop Chu II DSP: The Chu II DSP delivers superior treble sparkle and air. Cymbal crashes, snare snaps, and background instrument decays are easier to pinpoint. It gives music an open, exciting presentation without crossing into harsh territory.
My Take: If you love warmth, thick bass, and a relaxed, fatigue-free sound, the 7Hz Zero 2 is the safer all-rounder. But if you want clarity, faster sub-bass slam, and detailed vocal energy, the Chu II DSP provides a more engaging and technically capable sound.
DSP Features & App Integration (Chu II Exclusive)
The biggest functional differentiator in this comparison is the Chu II’s Type-C DSP engine.
With the Moondrop Link app (Android), the Chu II DSP gives you access to:
- Interactive EQ Profiles: Switch between Default, Bass+, V-shape, and Reference studio curves.
- Parametric Equalizer (PEQ): Fine-tune specific frequency bands, gain levels, and Q-factors directly on the hardware chip, saving your custom tuning across any device you plug into (PC, Mac, iPad, or Android).
- Low-Latency Mic: An inline microphone that draws power directly from the Type-C port, delivering clear call quality for work meetings and Discord chats.
The 7Hz Zero 2, being a strictly 3.5mm analogue IEM, relies entirely on your device’s internal DAC or whatever external dongle you attach to it.
My Take: The DSP cable makes the Chu II virtually future-proof for modern smartphones. You don’t need to spend extra money on a separate Type-C-to-3.5 mm adapter, and hardware-level EQ storage makes it a versatile Swiss Army knife for audio enthusiasts.
Gaming & Technical Performance
For competitive shooters (Valorant, CS2, and Apex Legends):
7Hz Salnotes Zero 2: Offers a wider soundstage and more natural acoustic spacing. Footsteps in open environments provide accurate distance cues, and the warmer tuning helps prevent ear fatigue from loud gunshots.
Moondrop Chu II DSP: Provides sharper directional imaging. Gun reloads, footstep textures on hard surfaces, and utility cues cut through high-intensity firefights with greater precision.
My Take: For casual and immersive gaming, the Zero 2’s wider soundstage feels more expansive. For fast-paced competitive esports, the Chu II DSP’s sharper treble clarity gives you faster acoustic reaction times.
Value for Money
| Metric | Moondrop Chu II DSP | 7Hz Salnotes Zero 2 |
| All-in-One Cost | Best (No extra dongle DAC needed) | Requires 3.5mm jack / separate dongle |
| Included Extras | Leatherette pouch + Mic cable | Wide assortment of eartips |
| Durability / Care | Metal shells + replaceable nozzles | Durable plastic, but non-removable filter |
- At ~$24, the Chu II DSP includes the IEMs, a mic-enabled Type-C DSP cable, and a protective carry pouch. You do not need to spend an extra $10 on a dongle DAC.
- At ~$22, the Zero 2 gives you the IEMs and plenty of ear tips, but if your phone lacks a 3.5mm jack, you will need to factor in the cost of an external Type-C DAC.
My Take: In terms of pure out-of-the-box value for modern smartphone users, the Chu II DSP offers higher overall value because the cable itself acts as an audiophile-grade DAC.
Is It Worth Buying? (Which One Should You Pick?)
Buy the Moondrop Chu II DSP if:
- Your smartphone has only a USB-C port, and you don’t want to carry dongles.
- You love an all-metal build with the security of unscrewable, cleanable brass nozzles.
- You have smaller ears and need a compact, low-profile fit.
- You enjoy crisp vocal clarity, detailed treble sparkle, and customizable app-based EQ.
Buy the 7Hz Salnotes Zero 2 if:
- You already have a dedicated 3.5mm audio setup, DAP, or desktop DAC/Amp.
- You are sensitive to bright treble and prefer a warm, smooth, fatigue-free sound with punchy mid-bass.
- You prefer a wider soundstage for movies and casual gaming.
- You want a lightweight, playful design with multiple colour choices.
Final Words
Both of these IEMs represent the absolute pinnacle of what is possible in the sub-$25 budget category.
If forced to pick one daily driver, my personal vote goes to the Moondrop Chu II DSP. The combination of its sturdy all-metal shell, hassle-free removable nozzle maintenance, ultra-comfortable ergonomic fit, and the sheer convenience of a built-in Type-C DSP DAC makes it the most complete, modern budget package on the market today.
However, if you are an analogue purist who wants a rich, warm, and relaxing sound with zero treble fatigue, the 7Hz Salnotes Zero 2 remains a benchmark that easily punches above its price class.
