In-Ear MonitorOverreview

THIEAUDIO Hype 4 MKII

ThieAudio rebuilt its cult 'Mini Hype 10' into a brighter, more technical 'mini Monarch MKIV' — and split its own fanbase over the leaner bass and forward treble.

12 sourcesUpdated
$399Typical US price

Score aggregates reviewer opinions across topics.

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THIEAUDIO Hype 4 MKII

The short version

What to know.

A $399 six-driver hybrid IEM (two 8 mm composite-diaphragm dynamic drivers in a second-generation IMPACT² 'subwoofer' plus four Knowles balanced armatures, 4-way crossover) that is a ground-up redesign of the 2024 Hype 4, voiced brighter, leaner and more technical than the warm original — a neutral-to-bright, sub-bass-boosted 'mini Monarch MKIV.' Reviewers broadly agree on an unusually wide, deep soundstage with pinpoint imaging, class-leading detail and resolution for the price, an excellent CNC-aluminum build with a premium modular cable (stock tips are the common gripe), easy drivability (18 Ω / 101 dB) that still prefers a clean, slightly warm source, and strong technical value at $399. They split — sometimes sharply — on the new signature: the bass is deep, fast and clean to most but lean and light on mid-bass slam to a vocal minority (and not the 'thunderous' set the marketing implies); the mids read as clean and natural to some, cool, dry and slightly recessed to others; and the elevated treble is an airy, detail-rich showcase to fans but too much — distracting or fatiguing on bright or poorly-mastered tracks — to treble-sensitive listeners, though most agree it stops short of outright sibilance. A warmer source, a tip swap or a little EQ is how most owners settle its brighter edges.

About this product

The 2025 Hype 4 MKII — a ground-up redesign of the 2024 Hype 4, not a mild retune. ThieAudio swapped the original's dual 10 mm dynamic drivers and Sonion balanced armatures for dual 8 mm composite-diaphragm drivers in a second-generation IMPACT² subwoofer (the same system as the flagship Monarch MKIV) plus a Knowles-only BA array (two RAB for the mids, an ED-33465 for the mid-treble, a RAD-33518 ultra-tweeter), pulled the bass cutoff in from ~200 Hz to a sharper 150 Hz, and traded the resin shell for CNC-machined aluminum with a modular cable — all at the same $399. The result is a brighter, leaner, more technical and transparent set than the warm, big-bass original; many who love the OG's fun tuning consider this a different IEM rather than an upgrade. Not the original `thieaudio-hype-4`.

The THIEAUDIO Hype 4 MKII is a $399 six-driver hybrid from ThieAudio — the in-house brand behind retailer Linsoul — and, despite the name, a complete redesign rather than a tweak of the beloved 2024 Hype 4. It pairs two 8 mm composite-diaphragm dynamic drivers in a second-generation IMPACT² 'subwoofer' (the same bass system as the flagship Monarch MKIV) with four Knowles balanced armatures, wrapped in a CNC-machined aluminum shell with a modular cable. Reviewers keep reaching for the same shorthand: a mini Monarch MKIV.

Where the original was a warm, fun, big-bass crowd-pleaser, the MKII is tuned brighter, leaner and more technical — sub-bass boosted, mid-bass pulled back, treble pushed up. The reviews are broadly positive: near-universal praise for its wide staging, pinpoint imaging, detail and standout metal build, and a strong value case at $399 (often ~$300 on sale). The arguments are about the new signature itself — whether the lean, fast bass is 'clean' or simply lacks the promised thunder, whether the mids are 'natural' or a touch dry, and whether the elevated treble is an airy showcase or just too much. Plenty of praise to average, and a real fault line to map.

A good fit for

  • Detail and technical listeners who want air, sparkle, wide staging and pinpoint imaging over warmth
  • Sub-bass fans who prize a clean, fast, textured low end over big mid-bass slam
  • Buyers chasing flagship-adjacent (Monarch MKIV) technical performance and a metal build for ~$399 (or ~$300 on sale)
  • Competitive gamers and detail-first listeners who benefit from strong separation and imaging
  • ThieAudio fans stepping up from budget sets who want a transparent, analytical-leaning tuning

Think twice if

  • You loved the original Hype 4's warm, fun, big-bass character — this is a cooler, leaner, different set
  • You're treble-sensitive or listen loud on poorly-mastered tracks — the elevated top end can fatigue
  • You want thick, warm, forward vocals or basshead slam and rumble
  • You'll only pair it with lean or bright sources, where it tips into a 'treble fest'
  • You want a long, proven track record — it's a new, deliberately polarizing 2025 release

The reviewer consensus

Agreement &
disagreement.

3 / 12topics divide opinion
3 Strong agreement5 Mostly agree3 Divided opinions1 Limited evidence

Common ground6

  • An unusually wide, deep soundstage for an IEM, with pinpoint imaging that competes with sets well above $400.
  • Class-leading detail and resolution for $399 — incisive and textured, a defining strength even critics concede.
  • A ground-up redesign that is brighter, leaner and more technical/transparent than the warm original (sub-bass boosted, mid-bass pulled back, treble pushed up).

Points of contention3

  • Bass: deep, fast and clean sub-bass (a feature) vs lean and dry — light on mid-bass punch, slam and weight, and not the 'thunderous' set the name implies.
  • Mids: clean, natural and honest (if slightly recessed) vs cool, dry and thin — 'sterile,' hollowed out by the treble.
  • Treble: an airy, extended, detail-rich showcase vs simply too much — distracting or fatiguing on bright / poorly-mastered tracks (most agree it's not outright sibilant).

A closer listen.

12 topics · 3 divided
Left: criticalRight: positiveTighter lines: more agreementDashed: limited evidence

Tonality

Leans positiveMostly agree
Reviewer sentiment10 supporting sources
CriticalNeutralPositive

Band: opinion spread · Dot: weighted average

A clear break from the warm, fun original: reviewers agree the MKII is brighter, leaner, more transparent and more technical — a neutral-to-bright, sub-bass-boosted 'mini Monarch MKIV.' The label varies (U-shaped, neutral-bright, 'warm-neutral on steroids,' even V/W-shaped), and a critical minority hears it as cool and dry rather than musical.

“The Hype 4 MKII is a neutral IEM with a pretty sweet sub-bass boost. It’s a U-shaped monitor with a highly transparent nature.”

Yagiz, Headfonia

“Overall, the Hype 4 MKII present a bright, energetic signature with a clearly analytical orientation, yet without becoming cold or sterile.”

ArcotondoSound, MobileAudiophile

“I’d define the profile of the MKII as warm-neutral on steroids.”

requiemreview, r/iems

Measured

THIEAUDIO voices it to a brighter, sub-bass-boosted target: a ~9 dB sub-bass shelf cut sharply at 150 Hz (in from ~200 Hz on the original), a ~400 Hz mid lift, and an elevated lower treble with an upper-treble peak around 15 kHz. On Joyce's Review's B&K 5128 database the MKII reads as a leaner, brighter U-shape than the original Hype 4.

Link to this topic

The hardware

Specifications.

Checked

Design

Type
In-ear monitor
Drivers
2 × 8 mm dynamic (composite diaphragm, Gen 2 IMPACT2 sub-woofer, pneumatic acoustic chamber) + 4 × balanced armature (Knowles: 2× RAB (low-mids), 1× ED-33465 (mid-treble), 1× RAD-33518 (ultra-tweeter))2DD + 4BA

Electrical

Impedance
18 Ω
Frequency response
5 Hz – 22 kHz

Connection

Cable
Detachable
Plugs supplied
3.5 mm, 4.4 mm balancedmodular

Manufacturer-published figures, not measurements · from thieaudio.com, linsoul.com.

Follow the evidence

Sources 12

1–6 of 12 sources

Read with context

Limitations & method.

As of

What to keep in mind 6

  1. This is a read of where opinion sits as of July 2026; the $300–500 IEM space moves fast, and newer rivals keep shifting the value math.

  2. It shares a name with the 2024 Hype 4 but is a ground-up redesign that sounds quite different — brighter and leaner — so check which version a listing or review actually means; many who love the original prefer it.

Where to buy Product & retailer links

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