audio-sound @ hatena

An audio review & news blog. The volume should not exceed 80 dB is recommended. I usually adhere to the safe-listening style by WHO. Please note that my aural impressions and interpretations of measurements are also made from a safe-listening style.

Open Audio Witch collaborates with Japanese popular online unit "Naruharu"! Part 1

Open Audio Witch naruharu


Up-and-coming IEM brand Open Audio has collaborated with the pair unit Naruharu to release the first limited edition Toyama collaboration model.


As of 10/21, the Toyama model is sold out due to its great popularity, but will be back in stock soon.



  • Click here for product information!
  • Click here for the product page of Toyama model!


What is Naruharu?

Naruharu is a two-person unit that posts videos, chats, and plays games on a daily basis.


Features of the Naruharu model

  • Design and colors designed with the Naruharu duo in mind
  • Special box with an illustration of Naruharu
  • Enclosed color paper-like card with a reproduction of Naruharu's signature


Open Audio Witch

  • Premium dual-driver hybrid configuration (one side)
  • 10mm composite diaphragm dynamic driver
  • Custom-tuned balanced armature driver
  • 2-way frequency split system
  • Transparent, full-bodied sound
  • Easy-to-drive
  • High-quality silver-plated cable
  • Impedance: 20 ohms
  • Frequency range: 10Hz to 20kHz
  • Sensitivity: 110dB
  • THD+N: <0.5%
  • Cable 4-core silver-plated copper cable



See below for a review article on the prototype model OpenAudio Witch.

  • Click here for the Toyama model product page!