Fearless Audio S6Rui Review: Ranked #185 of 263

Last updated: October 10, 2026

The Fearless Audio S6Rui ranks #185 out of 263 total In-Ear Headphones for sound quality. See all Headphones rankings for every top pick.

Brand: Fearless

Prices on this page were last checked October 10, 2026 at 5:37 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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#185 Fearless Audio S6Rui: $389.00 Linsoul eBay

Pros: Six balanced armature drivers per side earn a preference score of 65 in crinacle’s measurement, a serviceable match to the Harman target. A 20 ohm impedance and 113 dB sensitivity let it reach loud levels straight from a phone or dongle. It earns the same rating as the OpenAudio Mercury for noticeably less money.

Cons: A 2.7 dB standard deviation from target points to an uneven response that benefits from some EQ. The Fearless Audio S8F from the same maker rates higher for a modest step up in price.

BackClosed
Built-in MicrophoneNo
ConnectionWired
Deviation From Target2.70 dB standard deviation
Driver TypeBalanced armature
Drivers6 x balanced armature
Form FactorIn-ear
Frequency Response15Hz - 20kHz (Manufacturer specified)
Harman Preference Score65 (measured by crinacle, via AutoEQ)
Impedance20 ohms
Sensitivity113 dB
Tonal Tilt-0.55 (negative is warmer, positive brighter)
EQ preset to match the Harman target

Set a preamp of -6.5 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.

FilterFrequencyGainQ
Low shelf105 Hz+1.8 dB0.70
Peak166 Hz-4.4 dB0.48
Peak851 Hz+3.4 dB1.06
Peak2,720 Hz+2.4 dB3.00
Peak1,770 Hz-1.3 dB2.18
High shelf10,000 Hz+6.5 dB0.70
Peak5,650 Hz+6.2 dB2.53
Peak4,718 Hz-4.5 dB3.03
Peak8,599 Hz+3.3 dB2.26
Peak3,846 Hz-1.8 dB6.00

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