TRN BAX Electrostatic

TRN’s latest flagship model BAX comes with two Electrostatic drivers from Sonion, one BA driver from Knowles and one 10mm dual magnetic in-house dynamic driver.

The shells are made from aluminium-magnesium alloy, but the faceplates of the IEM are made from 304 stainless steel. TRN BAX has a semi-open design with openings on the faceplate.

TRN BAX also comes with 16 core silver plated cable in the box which has a swappable audio jack design, but you can only select one type of connector when ordering the IEM.

In its hybrid configuration, TRN BAX handles the mid-frequencies with custom tunes Knowles 29689 BA driver. The lows are handled with a third-generation 10mm dual magnetic dynamic driver whose magnetic density has been increased by 15% compared to the previous generation. The high-frequencies are handled with two Sonion EST drivers and this makes the price 312$ for the IEM.

Although the price seems high, especially for an IEM made by TRN, the BAX is the cheapest IEM on the market with EST drivers. The closest contender is the DUNU EST112 (489$) model with the same driver configuration if I’m not mistaken.


Impedance: 22Ω
Sensitivity: 118dB/mW
Frequency range: 7-40000Hz
Connection: 2-pin 0.78
Price: 312$