SoftEars Volume entry-level 2BA+1DD hybrid in ear monitor earphone

Parameters: 
Impedance: 5Ω@ 1kHz
Sensitivity: 123.7dB/Vrms@1kHz
Effective frequency response: 20- 20kHz (IEC60318-4)
Frequency range: 8- 40kHz(1/4 inch free field microphone, -5 dB)
THD:< 1%@ 1kHz
Shell: imported medical resin+aluminum alloy
Driver: 10mm dynamic +2 balanced armature
Dynamic diaphragm: PU flexible suspending+beryllium-plated