Thieaudio Monarch MK3 VS 64 Audio U4S

Youtube Video Summary

The 64 Audio U4s hits a compelling sweet spot: a 1DD+3BA hybrid around $1,100 that echoes the lush, bass-tilted character of the Nio while fixing key drawbacks. Packaging and accessories feel improved, with multiple tip options and the included M12 APEX module; APEX not only tailors bass but also relieves pressure for long sessions. Fit follows 64 Audio’s comfortable triangular shell; the vented DD asks for a slightly shallower insert than the all-BA models. Sonically, expect a sub-bass-oriented shelf and a treble profile that’s more lively and “zingy” than the Nio, with extra energy around the upper treble. The big caveat is 64 Audio’s muted 2–4 kHz region, which can set soprano vocals a step back on the stage.

Against the brand’s full-BA staples (think U12t/U6t), the U4s trades some pinpoint imaging and coherency for unmistakable DD slam and tactile “air pushing.” Extension at both ends is excellent, with upper-treble energy that makes micro-detail and reverb trails pop. It’s not the clean, conventional neutrality of something like a Monarch-style tuning; rather, it’s a deliberate, colored signature that delivers fun plus technical chops. Crucially, it fills a missing niche at its price and, in many respects, outperforms the pricier Nio, making the U4s a standout recommendation for listeners who want bass authority, sparkle, and engaging dynamics without going all-in on the flagship tier.

Youtube Video Summary

Thieaudio Monarch MK3 takes the flagship slot with swagger: a 2DD + 6BA + 2EST array and a 4-way passive crossover, centered on the Impact² isobaric push-pull dual 10 mm subwoofer. The shells are huge and gorgeous (plain backs at ~$1000, fancy backs around ~$1100), vented on the underside, and paired with a supple, interchangeable-plug cable (2.5 / 3.5 / 4.4). Despite the driver count, coherence is the headline: this isn’t a parts parade—it’s a single, surgically precise instrument.

Sonically, bass behaves like a well-tuned subwoofer in a treated room: tight, fast, and slammy without bloat. The real party trick is imaging and spatial “distance”—sounds lock into place with eerie specificity, making familiar tracks feel new. Instrument separation is crystalline, treble air is effortless, and the set is easy to drive yet scales—more power refines rather than merely getting louder. Tip rolling matters: stock foams/silicones are okay, Dekoni helps, Dunu S&S can fit oddly on these large shells, while Render tips seal the room and boost performance ~15–20%, supercharging the imaging and engagement.

Against the Monarch MKII (good, kept around), the MK3 feels like a different tier—the sort of tuning that glues ears to music and makes skipping tracks impossible. Accessories are minimal because the message is clear: you’re buying the sound, and it arguably feels underpriced for this level. Currently on pre-order, this is peak IEM energy—an endgame-grade, king-making performance that invites hyperbole and earns it.

Youtube Video Summary

Bass is where the Monarch MK3 steals the show: tight, textured, and rumbly with real slam and no bleed, giving male vocals a more natural heft while staying clean. The Prestige LTD pushes the low end back for a lighter hit but trades that for a more open, airy stage and superior layering—great for busy mixes like rock, metal, and classical. The Hype 2 mirrors the LTD’s bass balance and rumble conceptually, but lacks the same overall technical resolve, making the MK3 the better pick for pop, EDM, R&B, and hip-hop that benefit from weighty sub-bass.

Through the midrange, the LTD steps ahead on separation, detail, and note definition, presenting vocals slightly set back yet more airy and sparkly; female vocals especially shine. The MK3 counters with more weight and engagement on male vocals and a forward presence, though its stage isn’t as deep or spacious as the LTD (a modest vertical lift over Hype 2, but not a “$1k soundstage”). Up top, the LTD has the smoothest, best-extended treble with the most air and microdetail of the trio. All three excel at moderate volume, but none invites cranking like certain high-volume specialists.

As an all-rounder, the MK3 checks nearly every box yet misses that distinctive “special sauce” expected at its price; think ~15–20% uplift over Hype 2. The LTD delivers the bigger technical jump at roughly 25–30%, with staging, extension, and air taking the crown, making a strong case paired with a cheaper daily driver. The Monarch MK2 still earns a nod for its midrange/vocal magic if that’s the priority. Final word: both LTD and MK3 score an S; for those willing to spend, they’re easy to recommend—just match the tuning to the library and the qualities valued most.

Youtube Video Summary

Thieaudio Monarch MK3 steps up as a true flagship: a 2DD + 6BA + 2EST hybrid with high-grade Knowles/Sonion drivers, a gorgeous marbled faceplate, and—crucially—a vastly improved shell over MK2. Comfort moves from a 2-hour limit to all-session wear, and the stock package (solid cable with swappable terminations, foam and silicone tips) is well thought out. Tip choice meaningfully shapes performance; options like SednaEarfit Short or Comply foam push it toward its best.

Tuning follows a balanced, studio-leaning tonality with extra sub-bass warmth, delivering both clinical insight and genuine fun. Micro-detail is standout, bass is clean, textured, and physical (from Nirvana’s “Lithium” to modern hip-hop drops), and male vocals are among the most convincing heard on an IEM in this tier. Stage is wider and a bit taller than MK2, with excellent imaging, layering, and separation, keeping drums, bass guitar, and synth lines neatly organized without blunting impact.

For competitive gaming, the MK3 brings a tight soundstage, strong depth perception, and clear audio cue emphasis, offering precise 360° placement and adequate verticality. Versus Prestige Limited, it trades some sterile clinical edge for a more engaging, atmospheric presentation that reads distance and urgency better; compared to Yanyin Moonlight Ultra, it’s the more coherent pick for both games and music. While great mid-fi options like Zens Top, Orchestra Lite, or Yanyin Canon 2 remain strong, Monarch MK3 feels like the elevated, “dreamy” flagship experience—a new top choice for music enjoyment that also dominates in game when properly tipped.

Youtube Video Summary

The 64 Audio U4s hits a compelling sweet spot: a 1DD+3BA hybrid around $1,100 that echoes the lush, bass-tilted character of the Nio while fixing key drawbacks. Packaging and accessories feel improved, with multiple tip options and the included M12 APEX module; APEX not only tailors bass but also relieves pressure for long sessions. Fit follows 64 Audio’s comfortable triangular shell; the vented DD asks for a slightly shallower insert than the all-BA models. Sonically, expect a sub-bass-oriented shelf and a treble profile that’s more lively and “zingy” than the Nio, with extra energy around the upper treble. The big caveat is 64 Audio’s muted 2–4 kHz region, which can set soprano vocals a step back on the stage.

Against the brand’s full-BA staples (think U12t/U6t), the U4s trades some pinpoint imaging and coherency for unmistakable DD slam and tactile “air pushing.” Extension at both ends is excellent, with upper-treble energy that makes micro-detail and reverb trails pop. It’s not the clean, conventional neutrality of something like a Monarch-style tuning; rather, it’s a deliberate, colored signature that delivers fun plus technical chops. Crucially, it fills a missing niche at its price and, in many respects, outperforms the pricier Nio, making the U4s a standout recommendation for listeners who want bass authority, sparkle, and engaging dynamics without going all-in on the flagship tier.