Wired IEMs
Symphonium Audio Helios
72Great
$1,100
Full review dataSymphonium Audio Helios vs THIEAUDIO Monarch MKIV: which should you buy?
On aggregated review scores the THIEAUDIO Monarch MKIV comes out ahead with a HearWiki score of 84. The full breakdown - sub-scores, specs and what reviewers actually said - is below.
Our pick: THIEAUDIO Monarch MKIV - Outstanding overall at around $1149.
Wired IEMs
THIEAUDIO Monarch MKIV
84Outstanding
$1,150
Full review dataScore breakdown
Each axis is a 0–10 blend of what reviewers scored, not a lab measurement.
THIEAUDIO Monarch MKIV leads on 3 of 4 measures.
- Symphonium Audio Helios
- THIEAUDIO Monarch MKIV
HearWiki score
72
84
Sound
8.9
9.4
Value
6.7
7.6
Price (USD)
$1,100
$1,150
Generation & platform
The scores rank quality. This is the other question: is the newer one actually newer technology, or the same platform in a new shell?
Same generation
The THIEAUDIO Monarch MKIV is 4 years newer, but it is the same generation of hardware: nothing in the radio, the codecs or the noise cancelling separates them. Nothing separates them on convenience features either, so the choice comes down to tuning and price. For 4 years between them, that is a thin return - treat this as a restyle rather than a new platform.
- Helios2021
- Monarch MKIV20254 yr newer
Specifications
HeliosMonarch MKIV
- Type
- Wired IEMs
- Wired IEMs
- Price (USD)
- $1,100
- $1,150
- HearWiki score
- 72
- 84
- Released
- 2021
- 2025
- Availability
- Discontinued
- Sold new
- Driver
- balanced armature
- 2DD + 6BA + 2EST tribrid
- Driver type
- balanced-armature
- tribrid
- Driver configuration
- -
- 2DD + 6BA + 2EST
- Driver size
- -
- 8 mm
- Drivers per side
- -
- 10
- Impedance
- 8.5 Ω
- -
- Active noise cancelling
- No
- -
- Connector
- 2-pin 0.78 mm
- -
What reviewers said
Symphonium Audio Helios
The Symphonium Audio Helios is a premium all-balanced-armature wired IEM that delivers a forceful, detailed, and technically impressive sound, with a notable emphasis on bass impact and holographic imaging. It presents a demanding load requiring substantial amplifier power, and its angular, large shell may pose fit challenges for some users. Overall, it is a standout choice for critical listeners who favor an energetic, incisive presentation over a relaxed or warm tuning.
- Pro:Exceptional bass and treble extension for an all-BA design
- Pro:Holographic and precise soundstage with strong imaging
- Pro:Highly competitive sound quality in its price bracket
- Con:Requires significant power to perform optimally
- Con:Large, angular shell can be difficult to fit comfortably
- Con:Aggressive, gritty tuning may not suit listeners seeking warmth
THIEAUDIO Monarch MKIV
The Monarch MKIV is a flagship in-ear monitor built around a ten-driver tribrid configuration, blending dual 8mm dynamic drivers, six balanced armatures, and two electrostatic tweeters. It offers a studio-neutral sound signature with an additional switchable bass-boost mode for listeners who prefer a more impactful low end.
- Pro:Reference-grade neutral tuning with excellent clarity
- Pro:Versatile bass boost mode adds flexibility
- Pro:Detailed and extended treble from electrostatic tweeters
- Con:High price point limits accessibility
- Con:Requires a capable source to perform at its best
- Con:Large shell may not suit smaller ears
Summaries are AI-condensed and paraphrased from published reviews and specs - not original hands-on testing. More on our method.
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