In this article, I’m reviewing the Kinera Celest Plutus Beast IEM. Plutus Beast is a tribrid IEM with one bone conduction, one square planar driver and one balanced armature driver. It’s priced at $89.

Disclaimer: This sample was provided by HiFiGo for an honest review. All observations and opinions here are my own, based on my experience with the product.

Kinera Celest Plutus Beast

Specifications

Driver: 1BC+1BA+1SPD(Patented Planar Driver) Acoustic Structure.
Impedance: 8Ω.
Sensitivity: 108dB.
Frequency Response Range: 20Hz-20kHz.
Connector Type: 0.78mm 2-pin.
Termination Plug: 3.5mm or 4.4mm.

In the Box

• Kinera Celest Plutus Beast IEMs
• Detachable 0.78mm 2-pin silver-plated cable
• Zipper carrying case
• 6x pairs of silicone eartips
• Metal bookmark
• Cleaning tool

Design

The most captivating aspect of the Plutus Beast’s 3D-printed shells undoubtedly lies in its intricately hand-painted faceplates. There are 3 colourways: blue, golden and blue-gold. The body of the shells is glossy black and the overall construction quality is superb.

Plutus Beast’s stock SPC cable is uniformly braided and has a smooth clear sheath. It’s an attractive cable with aluminium components. It handles well and doesn’t suffer from microphonics. It’s a great cable and is of higher quality than we’re used to seeing bundled with an $89 IEM.

Problems With the Bone Conduction Driver

I’m going to start this section by addressing a real problem with the Kinera Celest Plutus Beast that nobody seems to be talking about – the bone conduction driver (BCD). When an object vibrates, it creates pressure waves in the surrounding medium, be it air, water or solids. The BCD is intended to enhance the low-frequency response, and it does—bass notes have added physicality and texture.

The problem arises from its sensitivity. Any slight bump sets off the BCD inside the shells which results in an annoying ringing resonance in your ears. In addition, the resonance of my own voice when talking can set the BCD off. Male voices, in particular, seem to set them off and it’s distracting and annoying – try chewing gum or listening to a podcast with 2 males conversing and you’ll hear exactly what I’m talking about. In my opinion, it’s a serious issue and the technology or at least the implementation of it needs improvement.

Sound

Gear used for testing includes the Earmen Angel, Simgot DEW4X and HiBy R3 II. Plutus Beast is an efficient IEM and does not need a powerful source.

Bass

The bass is the highlight of Plutus Beast’s sound for me and it’s where we see the real benefits of the BC driver. Bass notes are delightfully textured, physical and gritty. The bass is powerful and authoritative yet it’s still controlled in terms of quantity.

Moreover, the bass reproduction on the Plutus Beast extends impressively into the sub-bass region, providing a visceral experience that resonates deeply. It effortlessly reproduces low-frequency nuances and rumble, adding depth and dimension to the music.

Midrange

The midrange of the Plutus Beast is multifaceted and characterized by a blend of strengths and limitations. The upper midrange introduces a challenge, as it tends to veer towards a “shouty” quality. There’s also a tendency for vocals, particularly male ones, to resonate in a way that triggers the BC driver, resulting in an unnatural timbre.

It’s a midrange that presents a contrast of warmth and forwardness. At its best, this combination adds richness and depth, enhancing the overall musicality. Yet, during busier segments, the midrange can falter, exhibiting some congestion that compromises clarity and separation.

Treble

In the realm of treble performance, Plutus Beast exhibits some notable characteristics that shape its overall sonic profile. Most notably, its upper treble extension leaves something to be desired, resulting in a lack of airiness and sparkle. This inhibits detail retrieval, contributing to a darker overall tone that may not appeal to those seeking a more vibrant and energetic sound signature. On a positive note, the treble is smooth and non-fatiguing.

Soundstage & Technicalities

In terms of technical performance, the Plutus Beast is somewhat lacklustre. While the soundstage dimensions are standard, it has notable forward depth. Positional placement is average and lacks precision. Additionally, the instrument separation and layering are fairly ordinary for something in this price range.

Verdict

In conclusion, the Kinera Celest Plutus Beast is somewhat of a mixed bag. On one hand, it has exquisite design and build quality and it comes with a good stock cable and accessories. Furthermore, Plutus Beast has a visceral, exhilarating bass response that sets it apart from its peers.

Yet, amidst its strengths lie some challenges that temper its overall appeal. Issues with timbre and tonal balance cast a shadow over its performance, detracting from its coherence and fidelity. Particularly problematic is the unwanted ringing of the bone conduction driver, triggered by the resonance of vocals and certain instruments. It’s still a decent IEM for the money but I would hesitate to recommend it outright.