Short answer: the qdc Gemini. It ranks #391 of 1291 in-ear headphones by sound quality, rated 4.0/5, at $2,137. The Oriolus Monachaa ranks #553, rated 3.8/5, at $2,000, $137 cheaper, not enough of a saving to outweigh the sound-quality gap.
Why pick the qdc Gemini: Crinacle’s measurement gives it a preference score of 74, and it is rated above the ThieAudio V16 Divinity and the Noble Audio Kadence. The catch: Presence from 3 to 6 kHz falls almost 6 dB short of target, with a dip of about 9.6 dB near 5.5 kHz, which dulls vocal clarity and attack on guitars and snares.
The case for the Oriolus Monachaa: An all dynamic IEM with four dynamic drivers per side. The catch: It is sold mainly through European dealers.
Buy the qdc Gemini. It is rated higher for sound quality, and the $137 you would save on the Oriolus Monachaa does not close the gap.
Looking for alternatives? See the complete Headphones rankings.
Crinacle’s measurement gives it a preference score of 74, and it is rated above the ThieAudio V16 Divinity and the Noble Audio Kadence.
Shenzhenaudio $2,137.00 eBay
An all dynamic IEM with four dynamic drivers per side.
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Specifications Side By Side
| qdc Gemini | Oriolus Monachaa | |
|---|---|---|
| Price | $2,137.00 | $2,000 |
| Ranked | #391 of 1291 in In-Ear Headphones | #553 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 74 (measured by crinacle, via AutoEQ) | 72 (median of 4 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 2.23 dB standard deviation | 1.97 dB standard deviation |
| Tonal Tilt | -0.12 (negative is warmer, positive brighter) | -0.54 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-3.4 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+3.2 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Balanced armature | Dynamic |
| Drivers | 8 x balanced armature | 4 x dynamic |
| Impedance | 25 ohms | 24 ohms |
| Sensitivity | 112 dB SPL/mW | 111 dB SPL/mW |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | - |
| Built-in Microphone | No | - |
Frequency Response Compared
Both headphones’ measurements overlaid on the Harman target. Above the target sounds louder in that range, below it quieter. Each curve is the median of several independent measurements, shifted so its 500 Hz to 2 kHz average sits at 0 dB, so only the tuning is compared.
Measurement data: the qdc Gemini from aden, recode, soundignity, therollo9 and timmyv; the Oriolus Monachaa from dchpgall, hbb, jaytiss and smirk, all via squig.link.
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