Short answer: the Symphonium Audio Helios. It ranks #64 of 450 in-ear headphones by sound quality, rated 4.5/5, at $1,099; the DUNU Glacier ranks #164, rated 4.3/5, and costs $1,340, so there is little reason to consider the other one.
What the Symphonium Audio Helios does well: One of the smoothest in-ears measured, with a 1.57 dB standard deviation from the Harman target and a preference score of 80. The catch: The presence region from 3 to 6 kHz sits 3.5 dB below target, with a 6.3 dB dip near 6.95 kHz, so vocals and guitars lose a little bite and detail.
Buy the Symphonium Audio Helios. It is rated higher for sound quality than the DUNU Glacier and costs less, which makes it the one to get unless you need something the other one does better.
Want more options? Browse the full Headphones rankings.
Specifications Side By Side
| Symphonium Audio Helios | DUNU Glacier | |
|---|---|---|
| Price | $1,099.00 | $1,340.00 |
| Ranked | #64 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 | 80 (measured by HypetheSonics, via AutoEQ) | 77 (median of 14 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 1.57 dB standard deviation | 1.55 dB standard deviation |
| Tonal Tilt | +0.02 (negative is warmer, positive brighter) | -0.62 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-1.3 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+3.5 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Balanced armature | Hybrid (1 dynamic + 4 balanced armature + 4 electrostatic) |
| Impedance | 8.5 ohms | 43 ohms |
| Sensitivity | 104 dB/Vrms | 109 dB/mW |
| Frequency Response | 12Hz - 24kHz (Manufacturer specified) | 5Hz - 40kHz (Manufacturer specified) |
| Built-in Microphone | No | - |
| Drivers | - | 1 x dynamic + 4 x balanced armature + 4 x electrostatic |
| Weight | - | 0 lbs (17.5 g) per earbud |
Related Headphone Comparisons
More worthwhile head-to-heads for Symphonium Audio Helios:
- ThieAudio Monarch MKIII vs Symphonium Audio Helios
- Simgot EM6L vs Symphonium Audio Helios
- Symphonium Audio Helios vs ThieAudio Monarch MKIV
- Symphonium Audio Helios vs Letshuoer Mystic 8
- ThieAudio Monarch MKIV 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
Symphonium Audio Helios: $1,099.00 Headphones.com eBay
Pros: One of the smoothest in-ears measured, with a 1.57 dB standard deviation from the Harman target and a preference score of 80. Bass reaches all the way down, sitting only 1.3 dB under target at 30 Hz, so kick drums and synth bass keep their rumble from an all balanced armature design. Overall tilt is essentially flat, and listeners who like a warm, bass-forward balance are the best match. It earns a higher rating than the SoftEars Twilight and the HIFIMAN RE2000.
Cons: The presence region from 3 to 6 kHz sits 3.5 dB below target, with a 6.3 dB dip near 6.95 kHz, so vocals and guitars lose a little bite and detail. The ThieAudio Monarch MKIII costs about the same and carries a higher rating.
Full Symphonium Audio Helios review and specifications →
| Released | 2021 (5 years ago) |
|---|---|
| Back | Closed |
| Built-in Microphone | No |
| Connection | Wired |
| Deviation From Target | 1.57 dB standard deviation |
| Driver Type | Balanced armature |
| Form Factor | In-ear |
| Frequency Response | 12Hz - 24kHz (Manufacturer specified) |
| Harman Preference Score | 80 (measured by HypetheSonics, via AutoEQ) |
| Impedance | 8.5 ohms |
| Sensitivity | 104 dB/Vrms |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-1.3 dB at 30 Hz) |
| Tonal Tilt | +0.02 (negative is warmer, positive brighter) |
EQ preset to match the Harman target
Set a preamp of -2.8 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 | -2.6 dB | 0.70 |
| Peak | 1,245 Hz | -1.7 dB | 0.50 |
| Peak | 71 Hz | +3.6 dB | 0.56 |
| Peak | 6,561 Hz | +3.7 dB | 4.67 |
| Peak | 3,355 Hz | +2.2 dB | 2.99 |
| High shelf | 10,000 Hz | -7.3 dB | 0.70 |
| Peak | 276 Hz | +0.5 dB | 1.70 |
| Peak | 533 Hz | -0.4 dB | 2.28 |
| Peak | 4,907 Hz | +1.5 dB | 6.00 |
| Peak | 139 Hz | -0.3 dB | 2.01 |
- 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