THIEAUDIO MONARCH MKIV In-Ear Monitors Kaleidoglow

The Thieaudio Monarch MKIV are hybrid in-ear monitors with ten transducers per side, designed to articulate the entire spectrum around a coherent multi-way architecture. They combine two 8mm dynamic drivers for bass, six balanced armature drivers for midrange and treble, and two electrostatic tweeters for ultra-high frequencies, using 4-way passive filtering to ensure precise frequency distribution and controlled transition between each register.

They also feature a dual-profile tuning system, selectable directly on the ear cups. This approach allows the bass and low-midrange response to be adjusted according to the desired balance, while maintaining the structure and separation offered by the hybrid architecture.

Thieaudio Monarch MKIV: Dual-profile sound signature

The Monarch MKIV introduces a new selectable tuning profile on the back of the earphones. In Standard mode, the tuning adopts a neutral base inspired by studio monitoring. The sub-bass reaches around +10dB, but a sharp cut-off at 150Hz limits its interaction with the low-mid range, maintaining firm and fast bass while preserving the clarity of vocals and instruments between 150Hz and 1kHz. This restraint in the lower spectrum allows the treble to express itself with greater clarity, emphasising vocal intelligibility and reducing excessive upper harmonics, resulting in less fatiguing listening over time.

In Rumble mode, the transition to the lower midrange is smoother, enhancing the feeling of density. The sub-bass is boosted by up to +13dB, while the 200-500Hz range gains around +2dB, adding more substance to the bass lines. This setting favours a fuller, more enveloping sound, while maintaining the separation provided by the multi-way architecture.