Isol-8 SubStation F5 Axis black

ISOL-8 SubStation F5 Axis: mains conditioner with DC blocking

Some amplifiers hum even when nothing is playing. The noise does not come from the speakers but from the case: it is the transformer vibrating, disturbed by a DC component present on the mains. This version of the SubStation F5 combines two treatments in a single unit. An Axis circuit blocks this DC component before the outlets, and ISOL-8’s Transmodal filtering then cleans the power supply to seven devices, with sources and amplifiers kept separate.

The Axis circuit at the front end of the unit

Mains current is supposed to be alternating and symmetrical. Yet some household appliances with unbalanced consumption introduce a small DC voltage. A toroidal transformer, found in most amplifiers, reacts poorly to this: its magnetic core partially saturates, the windings vibrate and the chassis hums, regardless of the volume. The larger the transformer, the more audible the effect.

The Axis circuit sits upstream of the entire distribution system. It allows alternating current to pass while blocking the DC component, protecting all seven outlets at once. For a system with two monoblock amplifiers or a powerful integrated amplifier, a single SubStation F5 Axis replaces several individual blockers.

Separate filtering for sources and amplifiers

After the Axis circuit, the F5 Axis uses the same distribution arrangement as the SubStation F5. The outlets reserved for sources (network player, DAC, preamplifier) pass through a multistage Transmodal filter, and ISOL-8 limits cross-contamination between them: a device that feeds interference back into the mains does not directly contaminate its neighbour. These low- and medium-current outlets support a total of 6 A.

The high-current outlets supply amplifiers through a version of the filter with very low series resistance. An amplifier can momentarily demand far more current than its average consumption, and this filtering does not restrict those demands. The seven outlets share a continuous 15 A capacity.

The Transmodal filter works in differential mode, between live and neutral, and in common mode, between these two conductors and earth. The protective earth receives its own filtering through a choke wound by ISOL-8. Surge protection and a resettable circuit breaker complete the package.

Connection and construction

The inlet socket is selected when ordering: IEC C14 (10 A), IEC C20 (20 A) or Neutrik powerCON. With power amplifiers, the C20 or powerCON provides access to the unit’s 15 A capacity, whereas the C14 limits the total to 10 A, approximately 2,300 W at 230 V. ISOL-8 IsoLink Vertex and Vector cables are available with these terminations.

The SubStation F5 Axis is hand-assembled in Worcestershire, with chokes wound by ISOL-8, polypropylene capacitors and PTFE-insulated silver-plated copper wiring. The 10 mm machined aluminium front panel is available in silver or black. The case measures 450 × 375 × 132 mm.

Technical specifications

Overview

• Model: SubStation F5 Axis
• Type: passive mains conditioner with DC blocking
• Range: SubStation F

Mains conditioning and filtering

• DC blocking: integrated Axis ISOL-8 circuit, upstream of the outlets
• Filtering: multistage Transmodal, common-mode and differential-mode
• Cross-contamination control between connected devices
• High-current outlets: Transmodal topology with very low series resistance
• Earth circuit filtering: ISOL-8 wound choke

Outlets and power supply

• Number of outlets: 7
  • Outlets for low / medium-current source devices
  • High-current outlets for amplifiers
• Choice of mains inlet: IEC C14 (10 A), IEC C20 (20 A), Neutrik powerCON NAC3MPXXA
• Total continuous current: 15 A maximum shared across all outlets
  • With IEC C14 inlet: 10 A maximum
• Continuous current for low / medium-current outlets: 6 A maximum in total
• Supply voltage:
  • European version: 220–240 V AC
  • 120 V version: 100–127 V AC
• Frequency: 50 / 60 Hz

Protection

• Surge protection
• Resettable circuit breaker

Components and construction

• Components: ISOL-8 wound chokes, polypropylene capacitors, PTFE-insulated silver-plated copper wiring
• Front panel: 10 mm thick machined aluminium
• Finishes: silver or black
• Manufacturing: hand-assembled in Worcestershire, England

Dimensions and weight

• Dimensions (W × D × H): 450 × 375 × 132 mm
  • Depth excluding connectors
• Packaged dimensions: 555 × 500 × 300 mm
• Weight: 11.7 kg, to be confirmed for the Axis version
  • Packaged: 15 kg, to be confirmed for the Axis version