How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want a wired in-ear monitor built around a single, carefully tuned neutral sound for work, choose TRUTHEAR x Crinacle Zero; if you need a hybrid multi-driver set with a physical tuning dial you can flip between sound profiles for work, choose ooopusX Op.24.
• TRUTHEAR x Crinacle Zero — biggest strength: a dual dynamic-driver design with a claimed HRTF-aligned tuning that aims for a natural, full-bodied monitor-style sound rather than a cold, clinical one.
• TRUTHEAR x Crinacle Zero — biggest trade-off: it's a fixed-tuning wired set with no microphone or noise control, so you'll need a separate mic for calls.
• ooopusX Op.24 — biggest strength: a 2DD + 4BA hybrid with a physical dual-mode tuning dial and an independent dual-channel crossover, so you can switch sound character on the fly.
• ooopusX Op.24 — biggest trade-off: six drivers and a tuning dial mean a more complex set that's less of a "set it and forget it" pick than a simple single-profile monitor.
• Who the Zero is for: listeners who want one reliable, neutral wired monitor for focused work and gaming.
• Who the Op.24 is for: tinkerers who want multiple sound profiles and a mic-equipped Type-C option in one set.
The Zero is built around a dual dynamic-driver setup with a 10 mm driver, a dual polyurethane suspension composite liquid-crystal dome diaphragm, and an N52 magnet double-cavity internal magnetic circuit. That's a lot of engineering for a single-driver-type design, and the goal is clear from the spec sheet: a proper low-frequency gain paired with a high-frequency response that follows HRTF characteristics. In plain terms, TRUTHEAR is aiming for the objective accuracy of a professional monitor without the cold, rigid character that often comes with one. The overall timbre is described as natural and full of atmosphere. If you've ever put on a "flat" monitor and found it lifeless, that's exactly the gap this tuning is trying to close.
Where the Zero gets interesting is in how it's made. The cavity uses a DLP-3D printed shell from HeyGears with medical-grade high-transparency resin, plus a sandwich structure of front cavity, decorative panel, and a glue-dropping capped top that's UV-cured, hand-polished, and varnish-sprayed. The acoustic nozzle uses a filtering structure with a calculated RC frequency division, forming a hybrid double frequency division so the two dynamic drivers each handle their own band. TRUTHEAR also emphasizes phase consistency across the full frequency range, which matters because phase distortion is the usual culprit behind the unnatural feel of cheaper multi-driver sets. The cable is four strands of silver-plated wire on a universal 0.78 2-pin interface with a recessed female socket on the cavity, so swapping cables later is straightforward.
Who should buy it: anyone who wants one dependable wired monitor for long work sessions and gaming, values a neutral-but-lively tuning, and doesn't want to think about settings. The 10 ohm impedance and 20 Hz–39.5 kHz range make it easy to drive from a phone dongle or laptop jack. Who should skip it: if you need a built-in microphone for calls, or you want to change the sound signature depending on what you're doing, this isn't the set — there's no mic and no tuning switch.
The Op.24 takes the opposite approach: more drivers, more control. It packs two dynamic drivers and four balanced armatures into a three-way hybrid architecture, with a coaxial 10 mm + 8 mm dynamic driver pairing that ooopusX says cuts low-frequency distortion by roughly half an order of magnitude by letting differently sized units cover complementary bands. The diaphragm is a silicone composite carbon-fiber dome, impedance is rated at 15Ω in Mode 1 and 27Ω in Mode 2, sensitivity is 127 dB/Vrms, THD is under 1%, and frequency response spans 10 Hz–40 kHz. The cable is oxygen-free silver-plated.
Who should buy it: listeners who like experimenting, want a mic-equipped wired set for calls, and appreciate being able to flip sound profiles on the fly. Who should skip it: anyone who wants a single, predictable tuning they never have to adjust, or who prefers the simplicity of one driver type.
Side-by-Side: Which Should You Choose?
• Best for a fixed, neutral work tuning → TRUTHEAR x Crinacle Zero. One profile, dialed in, no decisions to make.
• Best for switching sound profiles on the fly → ooopusX Op.24. The physical dual-mode tuning dial is the deciding feature here.
• Best with a microphone for calls → ooopusX Op.24. The Type-C with mic variant covers voice work; the Zero has no mic.
• Best driver simplicity and phase consistency → TRUTHEAR x Crinacle Zero. Dual dynamic drivers with a stated emphasis on full-range phase matching.
• Best for driver-count enthusiasts → ooopusX Op.24. Two dynamic plus four balanced armatures in a three-way hybrid.
• Best for cable swapping → a tie. Both use a 0.78 2-pin interface with silver-plated stock cables.
• Best for easy driving from a laptop or dongle → TRUTHEAR x Crinacle Zero. At 10 ohm it's the lower-impedance, simpler load.
• Best for low-frequency distortion control → ooopusX Op.24. The coaxial 10 mm + 8 mm pairing is specifically aimed at that.
My Verdict
No — the Zero has no microphone and no noise control, so it's a listening-only wired monitor. For calls, the ooopusX Op.24's Type-C with mic variant is the practical pick.
That's a preference question. The Zero aims for a neutral, HRTF-aligned tuning with consistent phase; the Op.24 gives you two tunable profiles via a physical dial. If you want one signature, the Zero; if you want options, the Op.24.
Probably not. The Zero is rated at 10 ohm and the Op.24 at 15Ω in Mode 1 and 27Ω in Mode 2, both of which are easy loads for a laptop jack or a phone dongle.
Both carry a 1-year warranty and use 0.78 2-pin cables. The Zero's glue-dropping capped cavity with UV curing and hand-polishing is built for structural firmness, while the Op.24's 3D-printed cavity focuses on internal acoustic topology. Both are reasonable for daily desk use.
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