Fearless Audio is a Chinese company that specializes in in-ear monitors. I would like to thank Fearless Audio and Penon Audio for the review unit of S4. At the moment, you can purchase the S4 from Penon Audio.

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  • Driver Configuration: 4 Balanced Armature
  • Frequency Response: 20Hz – 20kHz
  • Impedance: 32 ohm
  • Sensitivity: 114dB/mW

Unboxing & Accessories

The S4 comes in a white package with a protective cover that sports the words, “CLASSIC NEVER ENDS”. Inside the package, there is a hard carrying case which contains the S4, detachable 0.78mm 2 pins cable, tips, cleaning cloth, instruction manual and warranty card.



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