The Symphonium Audio Helios ranks #57 out of 238 total In-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: Symphonium
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#57 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.
| 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 |
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