Furutech FI-8N NCF (R)
Overview
Many CD players, converters and compact network players make do with a two-pin figure-8 mains input, originally supplied with a thin, unassuming cord. This female connector terminates a higher-quality mains cable on this type of input, without using an intermediate adapter. Damped body with NCF material, rhodium-plated beryllium copper contacts: Furutech applies its high-end connectivity to a format that is often overlooked.
Terminate a cable on a figure-8 input
The figure-8 input, known as C8 or figure 8, is fitted to many sources and small double-insulated audio devices, without an earth pin. The FI-8N is the female part (C7) fitted to the end of a cable and plugged into it. Where some assemblies use an adapter connecting a standard IEC plug to a figure-8 input, it terminates the cable directly in the correct format, with one less contact in the current path.
The connector is rated at 7 A at 125 V and 2.5 A at 250 V. On domestic 230 V mains, this leaves a margin of around 575 W, more than enough for a player, converter, preamplifier or network player whose consumption is measured in tens of watts. Devices with high current requirements use another plug format, with three pins and earth, which this connector does not replace.
Rhodium-plated beryllium copper contacts
The part that really does the work in a female connector is the contact: it must grip the device pins with constant pressure, insertion after insertion. Furutech uses female conductors in α (Alpha) beryllium copper and phosphor bronze, two alloys selected for their elasticity, which maintain this pressure over time without loosening. The conductors undergo the in-house Alpha process (cryogenic treatment followed by demagnetization).
The rhodium plating, represented by the R in the name, covers these contacts with a hard metal that is resistant to wear and corrosion, maintaining a stable surface through repeated connections. Rhodium conducts slightly less well than gold by volume, but it wears much more slowly. Furutech offers the same connector in a gold finish, referenced (G), for those who prefer this trade-off.
A body damped by NCF material
The housing is made of glass-fiber-reinforced nylon, loaded with NCF (Nano Crystal² Formula) material, which distinguishes this version from the basic FI-8N. This compound combines nanometer-sized crystals, piezoelectric ceramic particles and carbon powder. Its practical function is mechanical: to damp vibrations and resonances travelling through the connector body that could be transmitted to the contacts. The material also has antistatic properties, limiting the buildup of charges on the surface.
Screw assembly and compatible cables
Connection is made using clamping screws, without a soldering iron: strip the cable, insert the conductors, tighten. The assembly can be redone if needed, making the part convenient for building or refurbishing a cord. The connector accepts cables from 6.0 to 13.0 mm in outer diameter, with conductors up to 2.4 mm in solid core or 2.0 mm² (14 AWG) in stranded wire. Firm tightening remains essential for good contact.
In terms of dimensions, the body measures 36.8 by 28.2 mm and is approximately 71.0 mm long, weighing 51.4 g. This is the standard size of the series, distinct from the slimmer FI-8.1N slimline, which accepts thinner cables and is connected by soldering. You will need a bare mains cable and a wall plug at the other end: the FI-8N only fits one end, on the device side.
Technical Specifications
Electrical Specifications
- Rated current: 7 A at 125 V AC
- Rated current: 2.5 A at 250 V AC
Nano Crystal² Formula (NCF) Technology
- Exclusive Furutech technology developed and used only in its products
- Main function: improved electrical and mechanical damping
- Antistatic action: special crystals generate negative ions that help reduce static electricity
- Thermal conversion: the crystalline material transforms thermal energy into far-infrared radiation
- Associated materials
- Nanometer-sized ceramic particles
- Carbon powder
- Piezoelectric-effect materials
- Result: reduction of unwanted vibrations and resonances for optimized electrical transmission
Conductors
- Type: Furutech-specific design of female conductors
- Material: α (Alpha) beryllium copper and phosphor bronze
- Finish: rhodium plating
- Objective: promote stable, high-quality electrical transmission
Body and Damping
- Main material: glass fiber-reinforced nylon
- Treatment: integration of an NCF anti-resonance damping material
- NCF material composition
- Nanometer-sized crystals
- Piezoelectric ceramic particles
- Carbon powder
- Function: limit vibrations and resonances likely to affect transmission
Cable Compatibility
- Compatible cable outer diameter: from 6.0 to 13.0 mm
Connection
- Connection type: clamping screws
- Maximum solid conductor diameter: 2.4 mm
- Maximum stranded conductor cross-section: 2.0 mm²
- Equivalent: 14 AWG
Dimensions
- Width: 36.8 mm
- Height: 28.2 mm
- Overall length: approximately 71.0 mm
- Tolerance: ± 0.5 mm
Weight
- Net weight: approximately 51.4 g
Frequently asked questions
What is the difference between the (R) rhodium version and the (G) gold version?
Both share the same NCF body and the same beryllium copper and phosphor bronze conductors. Only the contact plating differs. Rhodium is a hard metal: it withstands wear from repeated connections and corrosion well, at the cost of slightly lower bulk conductivity than gold. Gold, being softer, conducts slightly better but marks more easily. The choice mainly comes down to whether this durability is desired.
How does the FI-8N differ from the FI-8.1N slimline?
The FI-8.1N has a slimmer body, which is useful when space is limited behind the device or when several figure-8 sockets are side by side. It accepts thinner cables (5.0 to 10.5 mm instead of 6.0 to 13.0 mm) and is connected by soldering, whereas the standard FI-8N is secured with a screw. For a cable with a good cross-section, the FI-8N remains the most versatile.
Can it be used with a power amplifier?
Rarely, for two reasons. First, the current capacity: 2.5 A at 250 V tops out at around 575 W, which covers source components but not large amplifiers. Then there is the format: a power amplifier is almost always grounded and uses a three-pin plug, whereas the figure-8 is fitted to double-insulated devices without grounding. The FI-8N is intended for source components and small audio devices.
Is polarity important during installation?
The figure-8 connector has two poles and no earth. There is no required connection direction on the plug itself, but it is still useful to identify which conductor goes to which terminal, to maintain the same live and neutral correspondence from one end of the cable to the other, between the wall socket and the device. Careful assembly marks this reference before tightening.
Is a soldering iron necessary?
No. The connection is made using clamping screws. Simply strip the conductors to the required length, insert them into the terminals and tighten firmly. A loose contact heats up and degrades the connection: this is the point to watch. The assembly can be undone and redone, without consumables.
- Eco-contribution included in the sale price.
