Thieaudio has consistently proven that it knows how to deliver standout IEMs; whether that's the Oracle MKII, the Prestige LTD — which is still a great all-round musical option — or the flagship Valhalla, which is just on another level. But it's the brand's Monarch series that gets the most amount of attention, and deservedly so; I used the Monarch MKIII last year, and it didn't take long to realize that these IEMs are truly special.
That's why I was excited to get my hands on the Monarch MKIV; at the outset, the IEMs have a similar driver configuration that sees two dynamic driver, six Sonion balanced armature drivers, and two Sonion EST drivers in each shell, with a 4-way crossover and four sound tubes. Where things start to get interesting is the tuning switch, with Thieaudio adding a toggle on the IEMs that lets you easily switch between the reference neutral tuning and a much more engaging bass-focused sound. This Rumble mode (as it's called), adds a 3dB boost to the entire sub-bass range, making the overall sound that much warmer.
