Furutech FI-C15 NCF (R)
Overview
The Furutech FI-C15 NCF(R) is an IEC connector designed for audio installations with space constraints. It uses Nano Crystal² Formula technology and a pure α copper conductor plated with rhodium. This model, part of the FI-15 series, adopts a slim form factor to fit modern amplifiers and confined spaces.
A technical response to a practical problem
The FI-C15 NCF(R) measures 22.0 mm in height, 30.0 mm in width, and 82.2 mm in overall length. These compact dimensions are its main advantage: enabling the connection of devices whose IEC sockets are particularly hard to reach. LINN, Devialet, McIntosh, Mark Levinson amplifiers, and Micromega’s M-One series are among the equipment that directly benefit from this compact format, although many other modern devices share the same space constraint.
The connector body combines nylon and fiberglass, materials chosen for their rigidity and ability to absorb mechanical vibrations. This construction withstands shocks while maintaining dimensional stability over the long term. The clamping system uses polycarbonate for the cable clamp, with stainless steel screws that ensure a firm hold without risk of corrosion. The FI-C15 accepts cables with a diameter of 6.6 to 16.0 mm, corresponding to cross-sections up to 3.5 mm² (12 AWG).
Alpha copper and rhodium plating
At the heart of the FI-C15 is Furutech’s pure α (Alpha) copper conductor. This material is not ordinary copper: it is long-grain crystal copper obtained through a special continuous casting process, in which virtually all impurities have been eliminated at the microscopic level. The term “Alpha” refers to the cryogenic treatment and demagnetization applied to all metal components.
The Alpha treatment takes place in two stages. The first is deep cryogenic freezing of the metal parts at temperatures between -196°C and -250°C, using liquid nitrogen or helium. At these extreme temperatures, the metallic structure changes: molecules bond more tightly, internal stresses are released, and the whole becomes more stable. This transformation improves electrical conductivity and thus signal transfer.
The second stage exposes these same parts to the patented ring demagnetization treatment. Unlike ordinary powerful magnets, which often leave certain areas more magnetized than others, this process uses controlled attenuation to completely eliminate residual magnetization. The patent holder for this treatment is Sekiguchi Machine Sale Co., Ltd. in Japan; Furutech is a licensed user.
Rhodium plating covers this Alpha copper. Rhodium, a precious metal in the platinum family, has exceptional hardness and remarkable resistance to oxidation and corrosion. Although its conductivity is lower than that of pure gold, rhodium has the advantage of not oxidizing over time and maintaining a perfectly stable contact surface. Its balanced impedance across the entire frequency spectrum makes it a coherent choice for audio applications where neutrality is paramount.
Nano Crystal² Formula technology
The FI-C15 NCF(R) incorporates the Nano Crystal² (NCF) formula in its body, an exclusive technology developed by Furutech. This formula combines several active materials with complementary properties.
The first component is a special crystalline material with two so-called “active” properties. On one hand, it generates negative ions that neutralize static electricity. On the other, it converts thermal energy into far-infrared radiation. These two actions help stabilize the connector’s electrical environment.
This crystalline material is supplemented with nanoscopic ceramic particles and carbon powder. These elements exploit the piezoelectric effect: when subjected to mechanical stress, they generate an electrical charge that bridges electrical and mechanical oscillations. This effect effectively damps unwanted vibrations that can disturb the signal.
The carbon powder also has thermally conductive characteristics that interact with the charged ceramic particles, converting their energy into heat which is then dissipated through the surface of the connector body. This mechanism of interconversion between thermal, mechanical, and electrical energies forms the essence of Pure Transmission according to Furutech: electrical and mechanical damping acting simultaneously on multiple fronts.
Technical Specifications
Construction and Materials
- Conductor: α (Alpha) pure copper with rhodium plating
- Body: nylon / fiberglass with anti-resonance NCF material
- Nanoscopic crystals
- Ceramic particles
- Carbon powder
- Clamping system: polycarbonate with stainless steel screws
- Connection type: screw clamp
Compatibility
- Cable diameter: 6.6 mm to 16.0 mm
- Cable cross-section: up to 3.5 mm² (12 AWG)
- Compatible devices: LINN, Devialet, McIntosh amplifiers and other equipment with hard-to-reach IEC sockets
Dimensions
- Width: 22.0 mm
- Height: 30.0 mm
- Total length: 82.2 mm
NCF Technology
- Furutech exclusive Nano Crystal² (NCF) formula
- Special crystals generating negative ions to eliminate static electricity
- Conversion of thermal energy into far infrared to improve signal stability
- Nanoscopic ceramic particles and carbon powder providing a piezoelectric effect
- Reduction of unwanted resonances and vibrations
- Optimal electrical and mechanical damping
Highlights
- Slim, compact design for easier access to hard-to-reach IEC sockets
- Ultra-precise, stable power transmission
- Exclusive NCF technology to eliminate interference and vibrations
- Durable rhodium finish resistant to oxidation
- Compatible with audiophile cables up to 16 mm in diameter
Frequently Asked Questions
What’s the difference between the rhodium (R) version and other Furutech finishes?
Rhodium plating offers superior resistance to oxidation and a stable contact surface over time. Rhodium maintains its properties without degradation, unlike gold which, although more conductive, may exhibit a slightly different signature. The choice often depends on the system in which the connector will be used and personal preferences regarding tonal balance.
Why is a “slim” format necessary?
Modern amplifiers often adopt compact designs where IEC sockets are positioned in tight spaces, sometimes close to other connectors or walls. Standard IEC connectors cannot physically fit into these configurations. The FI-C15 solves this concrete problem without compromising connection quality.
What does the Alpha treatment really bring to the connector’s performance?
The Alpha treatment modifies the molecular structure of copper at a fundamental level. Cryogenic processing reduces internal stress and stabilizes the material, while ring demagnetization eliminates any residual magnetism that could interfere with the signal. These two stages work together to optimize conductivity and minimize distortion.
How does the FI-C15 NCF(R) compare to non-NCF versions?
The addition of the NCF formula introduces an extra level of electrical and mechanical damping that earlier versions do not possess. Ceramic particles and carbon powder actively work to reduce interference and vibrations, while the crystalline material combats static electricity. This combination represents the current state of Furutech’s developments in connector technology.
Can the FI-C15 be installed on any cable?
The connector accepts cables with an outer diameter of 6.6 to 16.0 mm, with conductors up to 3.5 mm² in cross-section. These specifications cover the majority of audiophile power cables. However, it is recommended to check the exact cable dimensions before purchase, particularly for large-diameter cables that may approach the upper limit.
Is NCF technology exclusive to Furutech?
Yes, the Nano Crystal² formula is proprietary technology developed and produced exclusively by Furutech. No other manufacturer can use this specific combination of crystalline materials, nanoscopic ceramic particles, and carbon powder in the proportions and configurations developed by Furutech. This exclusivity makes NCF a distinctive hallmark of the brand’s high-end products.
- Eco-contribution included in the sale price.