In this article, I review the EarAcoustic Audio SPA Hi End MAX IEMs. The Hi End MAX features a large 11.4mm titanium gold ball top+silicon crystal edge double-sided composite diaphragm and a flashy design. It’s priced at 289 USD.

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

Update (May 2025): Revised the rating for the EarAcoustic Audio SPA-Hi End Max to reflect its standing more accurately.

EarAcoustic Audio SPA Hi End MAX

Specifications

Model: SPA HiEnd MAX
Unit: 11.4 mm Titanium Gold Ball Top + Silicon Crystal Edge Double-sided Composite Diaphragm Double Magnetic Circuit Double Chamber Dynamic Coil Unit
Sensitivity: 109dB
Impedance: 30 ohms
Frequency response range: 5-40000Hz
Wire specification: 0.78 mm dual pin LITZ coaxial bundle, oxygen-free copper and silver plated wire mixed weave 1.20M

Inside the Box

• SPA Hi End MAX IEMs
• Detachable 0.78mm 2-pin cable
• Carrying case
• SPA lucky bracelet
• 3* pairs of narrow-bore silicone eartips (S, M, L)
• 3* pairs of wide-bore silicone eartips (S, M, L)
• Documentation

Design

Striking is one word I’d use to describe the EarAcoustic Audio SPA Hi End MAX shells. CNC-machined from aviation-grade aluminium alloy, they feature silver electroplating and a polished mirror finish. The faceplates sport a diamond-like texture that glitters under the light, topped with a crystal resin coating. The right faceplate bears the EarAcoustic logo, while the left showcases a snake motif commemorating the Year of the Snake.

There’s a large vent behind the 2-pin sockets and a smaller pinhole vent near the base of the nozzle. As a result, the Hi End MAX doesn’t create any ear pressure build-up—at least not for me. The nozzles feature a well-defined lip that holds eartips securely in place, and a stylish metal grille protects the nozzle opening, mirrored by the same grille on the larger vent.

The shells have a pseudo-custom shape and fit comfortably in my ears, despite their fairly large size. Passive noise isolation is average, providing distraction-free listening in most situations, though less effective in particularly noisy environments.

The SPA Hi End MAX comes with a somewhat chunky coaxial Litz cable made from a mixed oxygen-free copper and silver-plated copper. It handles well and feels premium to the touch but unfortunately is only available with a single-ended 3.5mm termination (future releases will offer a 4.4mm alternative).

Sound

Gear used for testing includes the HiBy R6 III 2025, iFi Zen DAC 3 and Shanling UA6. The EarAcoustic Audio SPA Hi End MAX is an efficient IEM that doesn’t need a powerful source, but its resolving nature benefits from a high-quality DAC.

The sonic character of the SPA Hi End MAX feels much like its shell design—it shines with sparkle and detail, yet there’s a sense of solidity and weight behind it. The sound is pristine and polished, just like the mirror-finish shells, but it also flows with graceful, smooth curves, echoing the sculpted form of the housings. It’s a blend of clarity and composure, wrapped in a presentation that’s both refined and assertive.

Bass

Bass is punchy and fast, with great definition and control. It doesn’t feel bloated or loose—just tight and well-behaved, with enough slam to give drums and basslines authority. And thanks to the large driver, there’s excellent sub-bass reach. It can rumble when called for, but without bleeding into the mids or muddying the stage.

Midrange

The midrange sits in a really nice spot—clear and natural, without sounding sterile or overly rich. Instruments have good separation and air between them, and the timbre is spot-on. Guitars have that nice combo of texture, body, and bite, with just the right amount of shimmer on the top end. Male vocals are full without being chesty, while female vocals have presence and energy but never stray into harshness— powerful and vivid, not shouty or sharp.

Treble

Treble is crisp and airy, with solid extension and no harsh peaks or big dips. It’s clean without being clinical, letting acoustic instruments shimmer and decay naturally. Hi-hats and cymbals have the right amount of zing and sparkle—detailed and lively, but never sizzling.

Soundstage & Technicalities

The soundstage feels open and spacious, giving everything room to breathe. The driver in the SPA Hi End MAX responds well to dynamic shifts and layering. Transients are snappy, resulting in good instrument separation and a natural edge to the attack—nothing sounds artificially sharp or overly softened.

Comparisons

Simgot EA1000

The EA1000 has a leaner sound signature. Its lows are tighter and slightly more defined but they have less impact than the SPA Hi End MAX. EA1000’s mids are more forward and vocals and instruments have a thinner note size. The Simgot’s treble is more forward in the mix, due to its attenuated bass level and is airier than the SPA Hi End MAX.

EA1000 sounds more spacious and has a wider soundstage but its notes don’t have as much density as the Hi End MAX. Both have a similar level of detail retrieval and resolution.

Moondrop Kadenz

The Kadenz has a more neutral and brighter presentation, which is due to its attenuated (but tighter) bass, thinner mids, and elevated presence region. The mids sound more spacious but lack some body and warmth compared to the Hi End MAX.

Kadenz can sound a bit edgy and fatiguing depending on your choice of music and isn’t as suitable as an all-rounder compared to the Hi End MAX. It has a wider soundstage but less depth and a lower resolution.

Verdict

The EarAcoustic Audio SPA Hi End MAX is more than just a flashy shell—it delivers a sound that’s just as polished and articulate. The Hi End MAX proves to be a versatile performer across genres, from orchestral pieces to modern electronic tracks. It’s got the technical chops to handle complex passages without breaking a sweat, but still manages to stay musical and engaging.

Build quality and design are standout features, with the shimmering faceplates and premium finish giving the set a true high-end feel. If you want a stylish IEM that doesn’t skimp on sonic performance, the SPA Hi End MAX is an IEM worth considering.