Furutech The Astoria Plus E 1.5m

Can a power cable change how an audio system sounds? That’s the technical challenge Furutech takes on with the Astoria Plus E, a refined evolution of a model that has been highly regarded for several years. This mains cable is part of the Japanese brand’s Studio Power series, a range originally designed for recording studios and now embraced by hi-fi enthusiasts. It has also received the VGP Award in Japan.

A conductor forged like a blade

The core of the Astoria Plus E is based on α (Alpha) PC-Triple C technology, developed by Furutech in collaboration with Furukawa. This OFC (oxygen-free copper) conductor with a purity higher than 99.996% undergoes a special forging process: variable pressures are applied tens of thousands of times to the metal, using a technique inspired by katana sword manufacturing. This process reorganizes the crystalline grain boundaries of the copper to align them longitudinally, promoting a smoother electron flow than with conventional OFC copper or even monocrystalline PCOCC, according to Furutech.

The cable uses three conductors, each consisting of 80 strands with a diameter of 0.18 mm. This fine multi-strand configuration offers appreciable flexibility when installing behind an audio rack, while maintaining a generous conductive cross-section.

Construction and anti-interference shielding

The conductors are insulated with flexible audio-grade PVC, using a classic color code (brown, light blue, green/yellow for ground). A black inner PVC sheath wraps the whole assembly before a shielding braid in OFC copper with a thickness of 0.12 mm. This protection against electromagnetic (EMI/RFI) radiation is completed by an outer RoHS-compliant sheath, with a diameter of around 12.8 mm, and a two-tone braided nylon jacket that adds robustness and visual identification.

The “E” version of the cable corresponds to the European variant, equipped with an FI-E11-N1(Cu) Schuko plug on the wall side and an FI-11-N1(Cu) IEC connector on the equipment side. These Furutech connectors use pure copper contacts with a double-layer copper surface treatment, an approach that favors raw conductivity rather than precious plating.

The Floating Field Damper system

Furutech equips the Astoria Plus E with its patented Floating Field Damper device (US patent 6,669,491 / EP1445837). The principle starts from an observation: the alternating current passing through a cable and its connector generates magnetic fields that oscillate at mains frequency. These fields in turn induce small electrical potentials in the metal parts of the connector (screws, clamping elements), creating parasitic “floating fields.” The Floating Field Damper links these different metal parts together via a conductive bridge and connects them to ground, thereby dissipating the unwanted potentials.

What changes compared to the original Astoria

The “Plus” version brings several changes compared to the previous model. The main cable clamp, formerly made of polymer, has been replaced with a non-magnetic stainless steel part. This evolution strengthens the mechanical grip on the cable and helps reduce microvibrations transmitted to the connector. The connectors also benefit from a revised surface treatment to optimize electrical contact. Furutech states that it has carried out a tonal rebalance of the whole, in collaboration with musicians and sound engineers based in Tokyo.

Position in the Studio Power range

Within the Studio Power series, the Astoria Plus E sits alongside the Empire Plus. Furutech distinguishes these two models by their sonic signature: the Astoria Plus is said to favor responsiveness, liveliness, and bass weight, while the Empire Plus aims for a more neutral balance with increased detail resolution. Both models share the same Alpha PC-Triple C conductor technology and the same Floating Field Damper system, but the Empire Plus uses conductors with a larger cross-section (45 strands of 0.32 mm versus 80 strands of 0.18 mm).

Technical specifications

Connectors and wiring

• Unplated copper connectors Furutech FI-11M-N1(Cu) and FI-E11-N1(Cu)
• Conductors: 80 strands of 0.18 mm α PC-Triple C x 3 conductors
• Shielding: 0.12 mm OFC copper braid

Materials and finishes

• Insulation: flexible audio-grade PVC (brown, light blue, green with yellow stripe)
• Inner jacket: black flexible audio-grade PVC
• Outer jacket: flexible audio-grade PVC compliant with RoHS
• Outer sleeve: two-tone braided nylon compliant with RoHS
• Main cable clamp: non-magnetic stainless steel

Dimensions and configuration

• Outer insulation diameter: approximately 3.5 mm
• Outer jacket diameter: approximately 12.8 mm
• Length: 1.5 m

Technologies and innovations

• α PC-Triple C forging process inspired by katana sword manufacturing
  • Pure OFC copper conductors, folded and compressed to improve current flow
• α (Alpha) conductive shielding to reduce radiated noise
• Flexible RoHS-compliant PVC jacket for vibration insulation and capacitance reduction
• Floating Field Damper
• Main cable clamp in non-magnetic stainless steel
  • Ensures a firmer mechanical grip
  • Reduces mechanical and electrical distortion
• Gold-plated connectors for optimal signal transfer

Available models

• Astoria Plus: speed, natural response, and deep bass
• Empire Plus: balance and extreme resolution to hear every detail

Recommended applications

• Amplifiers
• Mixing consoles
• Microphone preamplifiers
• High-fidelity recording and playback systems

Sonic advantages

• Complete sonic coherence from the lowest bass to the highest treble
• Wide dynamics, natural and expansive sound
• More precise, detailed, and emotional music
• Deeper noise floor, allowing every note to stand out clearly
• Better dynamic balance and enhanced emotional engagement
• Improved focus across the entire spectrum