In this feature, Nihal reviews the Effect Audio Signature Series II, a refresh of the company’s entry-level triple audio cable series, first launched in 2022. Pricing ranges from $199 to $299.
Disclaimer: This sample was sent to me in exchange for my honest opinion. Headfonics is an independent website with no affiliate links or services. I thank Effect Audio for their support.
Click here to read more about Effect Audio products we have previously reviewed on Headfonics.
This article follows our current scoring guidelines which you can read in more detail here.
Effect Audio’s Signature Series cables do not need any introduction. First launched in 2022 with the Ares S, Cadmus, and Eros S models, the Signature Series quickly gained popularity.
Later, Effect Audio expanded the lineup with various enhancements to these cables. Among these were upgraded 8-wire versions of the Ares S and Cadmus, as well as a special Cadmus Founder’s Edition.
Effect Audio also commemorated the Eros S with a 1st Anniversary Edition, celebrating the cable’s initial success.
Effect Audio has now introduced the second-generation Signature Series comprising 3 cables priced from $199 SRP.
The new generation builds on customer feedback and introduces key upgrades in build quality, hardware, and wiring configuration, along with noticeable sonic enhancements. Importantly, the series retains its accessible price point, continuing to prioritize value for money.
In this review, we’ll explore the three new models—Ares S II, Cadmus II, and Eros S II—examining their performance with a variety of IEM pairings. We’ll also compare them to the original Signature Series cables and some other cables.
Material & Geometry
Ares S II
The earlier Ares S cable featured a 4-wire, 24AWG design, but the new Ares S II has been changed to an 8-wire, 26AWG configuration with a proprietary Dual Variant QuantumCopper™ design that blends two distinct types of copper in unique bundles.
One strand employs a central solid core, while the other uses a double-layer multi-bundle design.
This dual structure creates a balanced, dynamic sound profile. Although the wire count of the Ares S II is higher, it remains remarkably flexible due to EA UltraFlexi Insulation.
Cadmus II
The Cadmus II cable has also evolved from a 4-wire, 24AWG setup to an 8-wire, 26AWG silver-plated copper configuration. Its structure is similar to the Ares S II, using a central core surrounded by six multi-sized silver-plated copper bundles.
Like the Ares S II, it features thicker wire but maintains a soft, flexible feel. Both Ares S II and Cadmus II share similar construction, thickness, and flexibility.
Eros II
The Eros S II cable is an 8-wire, 26AWG configuration crafted from ultra-pure OCC silver and copper Litz wires, making it the only hybrid model in the Signature Series.
It uses a proprietary Tri-Element synCompound design, incorporating a central pure silver core and six multi-sized core bundles of a silver copper alloy and pure copper.
This unique blend of pure silver, pure copper, and silver copper alloy achieves a wide-ranging, expansive sound profile.
Design
The new Signature Series II cables maintain the aesthetic of the original lineup with refined hardware details. The Eros S II shows the most noticeable update, featuring a darker, more sophisticated tone, while the Ares S II and Cadmus II retain a similar look to their earlier 8-wire versions.
The Ares S II sports a brushed copper finish with a clear PVC coating, highlighting a strand-like texture beneath that adds visual depth. The Cadmus II, with its pearly white color, has a soft shine and clear PVC coating, allowing a glimpse into its internal wiring.
The Eros S II has a distinct dark grey matte sleeve, accented by subtle silver sparkles for an understated, premium look. Though thicker than the others, the Eros S II remains flexible thanks to a less densely braided design.
The Y-split design across the Signature Series II cables incorporates forged carbon fiber with unique accents tailored to each model. Its weight has also been reduced by 20% over the Series I version.
The Ares S II includes flecks depicting hues of copper; the Cadmus II features glittery silver flecks, and the Eros S II blends copper and silver for a sophisticated touch. Though larger, the Y-split adds no extra weight to the cables.
Each Signature Series II cable comes with a sturdy rhodium-plated brass 4.4mm termination plug, also available in 2.5mm and 3.5mm options.
Effect Audio’s ConX technology enables easy swapping of connectors, allowing compatibility with a range of IEMs, including 2-pin, MMCX, and the Pentaconn Ear.
This adaptability makes pairing the Signature Series II cables with various IEMs effortless and convenient, enhancing usability across your collection.
Handling
All three Signature Series II cables share a soft, flexible feel and a relaxed braiding pattern that avoids excessive tightness or rigidity. This loose braiding makes the cables easy to handle, roll up, and store, as they resist tangling and maintain their coiled shape.
Both the Ares S II and Cadmus II are lightweight, while the Eros S II is slightly heavier and takes up more space.
Despite its extra weight, the Eros S II remains user-friendly and is the most visually premium of the three, making it the preferred choice for extended use. All three cables have minimal downward pull, allowing for comfortable use even on the go.
The Signature Series II memory ear hooks are relatively firm, with the Eros S II having the stiffest hook. While this adds a bit of structure, it can feel less adaptable and may require slight adjustments for a more comfortable fit, especially depending on the angle of IEM insertion.
Packaging & Accessories
Effect Audio has kept the packaging consistent across all three Signature Series II cables, with each presented in a box of the same size and color. The front of each box features engraved artwork of the corresponding Greek hero, along with the cable name.
A unique detail is the finish of the artwork: Ares S II features copper-only artwork, while Cadmus II and Eros S II showcase a mix of copper and silver—a thoughtful touch that adds distinction.
Inside, the cable is elegantly displayed, running vertically from top to bottom with the Y-split positioned at the center, facing up. The cable is securely nestled within a foam cutout, though it’s worth noting that none of the cables include a carrying pouch.
Performance & Impressions
The following sound impressions of the Effect Audio Signature Series II cables were completed using 64 Audio Fourte and THIEAUDIO Oracle MKIII alongside my main source, Lotoo’s Paw Gold Touch.
Summary
Starting with the entrant Ares S II, this cable embodies the qualities of a classic copper cable, delivering rich bass, warm midrange, and sparkling treble. The sound has a pleasing warmth, with mids that are enriched without compromising treble clarity.
The Cadmus II offers a more balanced sound profile, bringing subtle refinement across all frequencies, with added warmth in the midrange and a touch of energy in the upper frequencies. It also offers improved clarity and openness than the Ares S II.
The Eros S II builds on the strengths of Cadmus II, emphasizing detail and providing a more spacious, airy presentation that takes the listening experience to a new level.
Timbre
Ares S II introduces noticeable warmth to the sound, with enhanced sub-bass and mid-bass that feel rounded and textured, adding a solid, balanced foundation.
The lower midrange gains richness, giving weight and density to vocals and instruments. This warmth enhances the body without overwhelming the treble, which retains clarity and extension.
While adding warmth, Ares S II maintains a sufficient treble presence, handling micro-details effectively without sacrificing the upper frequencies—a common drawback in many copper cables.
Cadmus II stands out for its balanced finesse, preserving the IEMs’ original sound while refining it with added clarity and subtle warmth. While it’s not as warm as Ares S II, Cadmus II achieves a clean, detailed sound with an organic richness in vocals and fullness in instruments like strings and piano.
The silver-plated composition enhances midrange clarity and adds subtle excitement to the sound. The upper frequencies are smooth, clear, and spacious, sounding more expansive than Ares S II.
Cadmus II excels in micro-detail combined with a harmonious balance of warmth and clarity, delivering a rich yet controlled audio profile.
Eros S II combines the benefits of both copper and silver, offering a well-rounded improvement in multiple areas. The bass is tighter and more textured, with better layering and a controlled response.
In the midrange, transparency, and resolution shine through, with a touch of warmth enhancing detail without overpowering. The upper midrange is fluid and extended, adding depth to the overall sound, while the treble remains airy and detailed.
A hint of sparkle in the treble enlivens IEMs with a subdued top end, achieving an expansive, well-balanced sound signature that captures the best copper and silver qualities.
Staging & Imaging
Each cable in the Signature Series II offers a distinct approach to sound staging. The Ares S II’s copper design delivers a rounded, intimate soundstage that brings the music closer to the listener.
Although it sacrifices some width, this intimacy creates a highly engaging experience. The added depth provides enough room for instruments, preventing any sense of congestion while maintaining a compact, well-structured stage.
The Cadmus II offers a more expansive soundstage, focusing on width and height. Positioned between the Ares S II and the Eros S II, it creates a realistic, spacious feel with a well-balanced width and height.
The Cadmus II sounds more open and separated than the Ares S II, providing greater spatial clarity and an impressive sense of instrument separation without congestion. Its imaging capabilities further enhance spatial precision.
The Eros S II is the most technically advanced in the series, delivering a wide and deep soundstage for an immersive listening experience.
Its layering and imaging are exceptional, with instruments and vocals placed and separated with pinpoint accuracy across a broad, tall stage. The Eros S II also offers the highest resolution among the three cables, creating a rich, spacious sound that elevates the listening experience to its fullest potential.
Click on page 2 below for my recommended pairings and selected comparisons.