Short answer: a tie on sound quality. Both are rated 4.6/5 (#47 and #40 of 450 in-ear headphones), so choose on features and fit.
Why pick the ThieAudio Monarch MKII: A preference score of 81 from crinacle’s measurement and just 1.45 dB of deviation make it one of the most accurate in-ears available. The tradeoff: Those measurements show a 5.6 dB dip near 6.5 kHz and treble about 2.6 dB below target, which softens cymbal attack slightly.
Why pick the Tin HiFi C2: Across 15 squig.link measurements it reaches a preference score of 81.6 with a 1.42 dB deviation, close to neutral with a slight warm lean. The catch: The 10 to 16 kHz air band runs about 5 dB above target with a 6.2 dB peak near 11.9 kHz, which can make cymbals and hi hats sound a bit sharp to treble sensitive ears.
Buy the ThieAudio Monarch MKII or the Tin HiFi C2 on features: they are rated the same for sound quality at close to the same price.
Want more options? Browse the full Headphones rankings.
Specifications Side By Side
| ThieAudio Monarch MKII | Tin HiFi C2 | |
|---|---|---|
| Price | - | $59.99 |
| Ranked | #47 of 450 in In-Ear Headphones | #40 of 450 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 81 (measured by crinacle, via AutoEQ) | 82 (median of 15 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 1.45 dB standard deviation | 1.42 dB standard deviation |
| Tonal Tilt | -0.22 (negative is warmer, positive brighter) | -0.07 (negative is warmer, positive brighter) |
| Connection | Wired | Wired |
| Driver Type | Hybrid (1 dynamic + 6 balanced armature + 2 electrostatic) | Dynamic |
| Drivers | 1 x 10mm dynamic + 6 x balanced armature + 2 x electrostatic | 1 x 10mm dynamic |
| Impedance | 36 ohms | 32 ohms |
| Sensitivity | 108 dB/mW | 104 dB @ 1kHz 0.179V |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | 10Hz - 20kHz (Manufacturer specified) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-0.3 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (-2.0 dB at 30 Hz) |
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- Tin HiFi C2 vs Kefine Klean
- Tin HiFi C2 vs Tin HiFi C2 2025
- DUNU Kima Classic vs ThieAudio Monarch MKII
Prices on this page were last checked October 11, 2026 at 4:59 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Headphones In Full
ThieAudio Monarch MKII AliExpress eBay
Pros: A preference score of 81 from crinacle’s measurement and just 1.45 dB of deviation make it one of the most accurate in-ears available. Across 19 hobbyist measurements on squig.link, sub-bass and bass sit within half a dB of target down to 20 Hz, so kick drums and synth bass have full, tight weight. Its 108 dB/mW sensitivity and 36 ohm impedance mean a phone drives it easily, and the hybrid layout combines a dynamic woofer, six balanced armatures and two electrostatic tweeters.
Cons: Those measurements show a 5.6 dB dip near 6.5 kHz and treble about 2.6 dB below target, which softens cymbal attack slightly. Air above 10 kHz rises about 3.4 dB over target, peaking near 11.8 kHz, which listeners sensitive to treble may hear as a touch of glare.
Full ThieAudio Monarch MKII review and specifications →
| Released | Oct 2021 (5 years ago) |
|---|---|
| Back | Closed |
| Connection | Wired |
| Deviation From Target | 1.45 dB standard deviation |
| Driver Type | Hybrid (1 dynamic + 6 balanced armature + 2 electrostatic) |
| Drivers | 1 x 10mm dynamic + 6 x balanced armature + 2 x electrostatic |
| Form Factor | In-ear |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) |
| Harman Preference Score | 81 (measured by crinacle, via AutoEQ) |
| Impedance | 36 ohms |
| Sensitivity | 108 dB/mW |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-0.3 dB at 30 Hz) |
| Tonal Tilt | -0.22 (negative is warmer, positive brighter) |
EQ preset to match the Harman target
Set a preamp of -3.6 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by AutoEQ from its measured frequency response.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | +0.1 dB | 0.70 |
| Peak | 6,833 Hz | +3.8 dB | 2.05 |
| Peak | 2,005 Hz | -1.3 dB | 1.08 |
| Peak | 319 Hz | -0.9 dB | 1.20 |
| Peak | 9,387 Hz | +2.0 dB | 3.00 |
| High shelf | 10,000 Hz | -2.6 dB | 0.70 |
| Peak | 4,445 Hz | +2.7 dB | 6.00 |
| Peak | 5,134 Hz | -2.0 dB | 6.00 |
| Peak | 811 Hz | +0.4 dB | 2.29 |
| Peak | 81 Hz | +0.3 dB | 1.93 |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
Tin HiFi C2: $59.99 Amazon eBay
Pros: Across 15 squig.link measurements it reaches a preference score of 81.6 with a 1.42 dB deviation, close to neutral with a slight warm lean. Bass from 60 to 200 Hz is lifted about 1.4 dB for punch while the midrange stays on target, so vocals sound clear and natural. It is rated higher than the Moondrop Lan and the pricier Moondrop Golden Ages 2, and its 32 ohm load runs easily from a phone.
Cons: The 10 to 16 kHz air band runs about 5 dB above target with a 6.2 dB peak near 11.9 kHz, which can make cymbals and hi hats sound a bit sharp to treble sensitive ears. A 3.5 dB dip near 6.5 kHz slightly blunts the leading edge of instruments.
Full Tin HiFi C2 review and specifications →
| Released | Jun 2023 (3 years ago) |
|---|---|
| Back | Closed |
| Connection | Wired |
| Deviation From Target | 1.42 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 10mm dynamic |
| Form Factor | In-ear |
| Frequency Response | 10Hz - 20kHz (Manufacturer specified) |
| Harman Preference Score | 82 (median of 15 squig.link measurements, calibrated to AutoEQ) |
| Impedance | 32 ohms |
| Sensitivity | 104 dB @ 1kHz 0.179V |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-2.0 dB at 30 Hz) |
| Tonal Tilt | -0.07 (negative is warmer, positive brighter) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons