Short answer: the ThieAudio Monarch MKIV. It ranks #105 of 450 in-ear headphones by sound quality, rated 4.4/5, at $1,149; the DUNU Glacier ranks #164, rated 4.3/5, and costs $1,340, so there is little reason to consider the other one.
Why pick the ThieAudio Monarch MKIV: Across 14 squig.link measurements it posts a preference score of 79.0 with a very smooth 1.31 dB spread. Watch for: Presence sits 2.7 dB below target with a 3.7 dB dip near 6.4 kHz, so vocals and strings lose some immediacy.
Buy the ThieAudio Monarch MKIV. It is rated higher for sound quality than the DUNU Glacier and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Looking for alternatives? See the complete Headphones rankings.
Specifications Side By Side
| ThieAudio Monarch MKIV | DUNU Glacier | |
|---|---|---|
| Price | $1,149.00 | $1,340.00 |
| Ranked | #105 of 450 in In-Ear Headphones | #164 of 450 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 79 (median of 14 squig.link measurements, calibrated to AutoEQ) | 77 (median of 14 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 1.31 dB standard deviation | 1.55 dB standard deviation |
| Tonal Tilt | -0.43 (negative is warmer, positive brighter) | -0.62 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-0.2 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+3.5 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Hybrid (2 dynamic + 6 balanced armature + 2 electrostatic) | Hybrid (1 dynamic + 4 balanced armature + 4 electrostatic) |
| Drivers | 2 x 8mm dynamic + 6 x balanced armature + 2 x electrostatic | 1 x dynamic + 4 x balanced armature + 4 x electrostatic |
| Sensitivity | 100 dB | 109 dB/mW |
| Frequency Response | 10Hz - 44kHz (Manufacturer specified) | 5Hz - 40kHz (Manufacturer specified) |
| Built-in Microphone | No | - |
| Impedance | - | 43 ohms |
| Weight | - | 0 lbs (17.5 g) per earbud |
Related Headphone Comparisons
More worthwhile head-to-heads for ThieAudio Monarch MKIV:
- ThieAudio Monarch MKIII vs ThieAudio Monarch MKIV
- ThieAudio Monarch MKII vs ThieAudio Monarch MKIV
- Symphonium Audio Helios vs ThieAudio Monarch MKIV
- ThieAudio Monarch MKIV vs Letshuoer Mystic 8
- Symphonium Audio Helios vs DUNU Glacier
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 MKIV: $1,149.00 Linsoul eBay
Pros: Across 14 squig.link measurements it posts a preference score of 79.0 with a very smooth 1.31 dB spread. Sub-bass and bass sit within half a dB of target, so the dual 8 mm dynamic drivers give clean, accurate low end, and a 5 dB air lift near 12 kHz from the electrostatic tweeters adds shimmer and space. It rates above the SoftEars RSV.
Cons: Presence sits 2.7 dB below target with a 3.7 dB dip near 6.4 kHz, so vocals and strings lose some immediacy. The Moondrop Dark Saber rates well above it for less money, and the Symphonium Audio Helios rates higher at a similar price.
Full ThieAudio Monarch MKIV review and specifications →
| Released | Jul 2025 (1 year ago) |
|---|---|
| Back | Closed |
| Built-in Microphone | No |
| Connection | Wired |
| Deviation From Target | 1.31 dB standard deviation |
| Driver Type | Hybrid (2 dynamic + 6 balanced armature + 2 electrostatic) |
| Drivers | 2 x 8mm dynamic + 6 x balanced armature + 2 x electrostatic |
| Form Factor | In-ear |
| Frequency Response | 10Hz - 44kHz (Manufacturer specified) |
| Harman Preference Score | 79 (median of 14 squig.link measurements, calibrated to AutoEQ) |
| Sensitivity | 100 dB |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-0.2 dB at 30 Hz) |
| Tonal Tilt | -0.43 (negative is warmer, positive brighter) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
DUNU Glacier: $1,340.00 Amazon eBay
Full DUNU Glacier review and specifications →
| Released | Apr 2024 (2 years ago) |
|---|---|
| Back | Closed |
| Connection | Wired |
| Deviation From Target | 1.55 dB standard deviation |
| Driver Type | Hybrid (1 dynamic + 4 balanced armature + 4 electrostatic) |
| Drivers | 1 x dynamic + 4 x balanced armature + 4 x electrostatic |
| Form Factor | In-ear |
| Frequency Response | 5Hz - 40kHz (Manufacturer specified) |
| Harman Preference Score | 77 (median of 14 squig.link measurements, calibrated to AutoEQ) |
| Impedance | 43 ohms |
| Sensitivity | 109 dB/mW |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+3.5 dB at 30 Hz) |
| Tonal Tilt | -0.62 (negative is warmer, positive brighter) |
| Weight | 0 lbs (17.5 g) per earbud |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons