Is the ThieAudio Monarch MKIV a True Upgrade from the MKIII?

SOUNDSTAGE & IMAGING

Sonically, are there any differences between the Monarch MKIV and MKIII? Being that they have slightly different driver makeups, there are key differences between them that you will find when listening side to side. Both IEMs showcase a very wide horizontal soundstage, one that wraps around your head and makes sure you are immersed in your listening. The Monarch MKIII displays a good frontal presentation that allows you to appreciate everything from bass to treble. The sound layers backwards and creates good depth, but stays mostly forward and stretches upwards to present good height in the wall of sound. The Monarch MKIV also has excellent horizontal presentation, and it expands further backwards for a deeper and even more immersive listening experience.

The Monarch MKIII has excellent imaging and separation, and the MKIV carries that to its newer tuning. On top of that, the Monarch MKIV has more distinct separation in its depth of layers that allows you to focus on individual elements of the tracks. The Monarch MKIII's wall of sound was a little less powerful than that of the MKIV, though it still provided excellent detail and precision in a host of genres. The Monarch MKIV impressed just a bit more, showing how the extended sub-bass can aid in making the soundstage more realistic while still being pretty decently spaced out. You can hear the open space in the top end that allows frequencies to ring out more naturally and keep the signature from sounding too heavy or compressed. 

Overall, I found the Monarch MKIII and the MKIV to be good for different use cases. I may reach for the Monarch MKIII if I wanted a more balanced, reference sound that was good for analytical listening. While the Monarch MKIV is also a good contender for analytical listening, the powerful bass response makes it amore favorable choice for bassheads and people looking for a fun IEM to accompany their day-to-day listening.

BASS FREQUENCIES

The bass response is where I found the main differences between the two Monarch IEMs. The MKIII produces a great bass response that is thick and punchy, taking up plenty of space in the low end and building a good foundation for other frequencies to build up from. I liked the control of the low end, where you got intense punchiness and thick layering. The sub-bass rumble was subtle, not the most intense response from what I've experienced in the past, but it is still powerful to make rock and pop tracks that much more driving and powerful. It matches the smooth reproduction of jazz ensembles and R&B songs to create a more realistic environment.

The Monarch MKIV shares many of the MKIII's bass frequency qualities. It was impressive how the low end built up from an extended sub-bass, rising up to capture tonal and textural details of the sound. It is thick but still controlled, so you don't get just the bass response when you listen to tracks. The low end was great for really driving the high-energy tracks forward, recreating more textural elements. The tones of 808 drums and low bass guitars were clear and crisp, so you got to appreciate all the finer details without sacrificing body or depth. The Monarch MKIV comes with an interesting and unique feature of a bass rumble switch. When this switch is turned on, the lower-mids get extended repsonse and the sub-bass becomes more accentuated. For people who want the extra push in the sub-bass and lower mids, it's a great feature that you have the option to turn on and off. 

MIDRANGE FREQUENCIES

One thing you can guarantee out of ThieAudio in-ear monitors is a detailed midrange. Between the Monarch MKIII and the Monarch MKIV, the midrange response is full of detail and texture that is great for any genre. Their differences are subtle, and they share more qualities than showcase differences. In the Monarch MKIII, you hear more of a midrange push forward than you do in the MKIV. The Monarch MKIV has frequencies pushed more to the back to let the treble and bass be the stars of the show. The midrange still has a lot of timbral detail that makes instruments easy to recognize, and with the layering that the Monarch MKIV has, it makes the midrange very rich and deep in color and texture. 

The sound reproduction sounds more natural in the Monarch MKIII. Because it gets slightly pushed forward, you can hear the detail and timbres of instruments with pristine clarity. Vocals get a special feature, filtering right to the front and center so you immediately notice when it comes in. The Monarch MKIV does have a lot of midrange detail, and the vocals come to the front in a good way. The Monarch MKIII has everything at a pretty equal playing field, and because it doesn't have the same level of depth as the MKIV, it feels thinner and almost brighter. It doesn't have the same warmth, but the detail and textural detail are very similar. 

TREBLE FREQUENCIES

Amidst all the depth and warmth of the low end, there is a brightness that comes from the treble response. Both the Monarch MKIV and MKIII come with incredibly detailed and precise high ends. With the balance that the Monarch MKIII provides, it is a bit easier to pick apart and appreciate the treble detail. You have a lot of space at the top end that expands far up into the ultra-highs, making the entire signature in the MKIII lighter and a bit more breathable. It is easy for IEMs to sound overwhelming and compressed, but when the treble lightens everything, it makes it easier to listen to the earphones for longer. This is especially true in the Monarch MKIII, and it is also true in the Monarch MKIV.

The Monarch MKIV's treble response is equally as important and impressive. Because the MKIV is a bass-heavy IEM, the treble has a lot of work to do to make sure it is heard and not lost in a sea of low frequencies. The treble does a great job in making sure you can hear all the details and space the top end has to offer, even against the strong low end. Reverberations echoed up and outwards in the depth of the sound signature, taking advantage of the height and really ringing out naturally. The cut-off was not awkward or sudden; instead, I could hear the space around the instruments and really picture more the ambient space as opposed to the instruments alone. The Monarch MKIII had some similar qualities, but the depth of the MKIV made this airiness much more pronounced, especially in the face of a thicker low end.