FiiO LL-RC 3M Headphone Cable with Furukawa Monocrystalline Copper

The FiiO LL-RC (2024) is a 3m headphone cable made from secondary-refined, high-purity Japanese Furukawa monocrystalline copper: 560 wires in a coaxial braid, silver-bearing lead-free solder, dual 3.5mm connectors for the ear cups and swappable 3.5mm single-ended and 4.4mm balanced plugs. It suits headphones with two 3.5mm sockets, such as the FiiO FT1 and FT3.

Every part considered

A high-end headphone cable should be high quality in every respect. FiiO drew on seventeen years of acoustic design to choose the materials, processing, build and ergonomics that let your headphones reach their full potential.

The sound

• Transparent mids: smoother, denser mids for clearer, cleaner vocals.
• Robust bass: more bass, and better quality, for livelier music.
• Enhanced dynamics: a much wider dynamic range while keeping the original soundstage, so large works such as symphonies are more enjoyable.
• Overtones: faster transients let you hear subtle overtones for a more three-dimensional sound.
• Clarity: the signal, especially the high frequencies, travels more efficiently and without loss, bringing you closer to female vocals and orchestral music.

Genuine Furukawa copper, refined twice

The copper comes from Furukawa Denki Industrial Co., Ltd in Japan, with official certification. It is heated continuously for 48 hours to reach 1,050°C and melt, held at a constant sintering temperature for 744 hours so that impurities sink to the bottom of the furnace, and taken through more than 70 complex processes, reducing pores, impurities and grain boundaries so the signal travels more freely. More than 70 steps of drawing and forging then turn it into high-purity monocrystalline copper wire just 0.05mm across.

560 wires in a coaxial braid

More wires mean a larger cross-section, lower resistance and better conductivity: the LL-RC has 560 wires across four strands, 21AWG in total, which is rarely seen. Inside each large strand, 25 wires of 0.05mm copper form a small strand and eight small strands (200 wires) carry the positive signal; an outer layer of 0.08mm copper wires shields them from interference. After many tests, FiiO found that combining 0.05mm wires (the thinnest that keeps crystal integrity) with lower-resistance 0.08mm wires gave the best sound, with lusher mids and clean, transparent vocals.

Silver solder and one-way welding

Silver-bearing lead-free solder lets the signal flow with minimal loss, for a more transparent, fuller sound. Because high-purity monocrystalline copper grains are directional, the cable is welded in one direction, following the crystal grains, so the signal flows freely and every cable sounds the same.

Braided nylon, built to last

A TPE inner sheath sits under a high-quality braided nylon outer sheath, flexible but durable enough for bending and rolling. FiiO makes the LL-RC in 1.5m and 3m lengths; this 3m version suits listeners who need more reach, gaming or recording studios. A hook-and-loop cable tie keeps it tidy.

Swappable 3.5mm and 4.4mm plugs

The cable comes with 3.5mm single-ended and 4.4mm balanced plugs, so you can switch to suit your source. The swappable plug design is licensed from FABRILOUS’s patent.

Good to know

• For headphones with dual 3.5mm sockets, not 2-pin or MMCX earphones.
• In the box: the 3m cable with 3.5mm and 4.4mm plugs.