Mains Cables R Us has been building mains filters for many years; and we can supply them from as little as £40 for a basic single-component filter, up to £2000 for a full-system filtering solution.

Showing 1–12 of 26 results

Black Ravioli Groundworks MA

  • Single unit with fused IEC plug terminal
  • Only to be used with the supplied mains connecting cable
  • Dimensions: 266x151x60mm
  • Weight: 2.35kg
  • Made in Scotland
For an overview of what the Black Hole Concept can achieve: click here

Black Ravioli Groundworks SA

  • 3 outputs
  • USB A, RCA, 6mm Spade, 4mm plug or HDMI with three 1 metre leads
  • Dimensions: 1288x151x60mm
  • Weight: 2.35kg
  • Made in Scotland
For an overview of what the Black Hole Concept can achieve: click here

CAD Ethernet Control

The CAD Ethernet Control is designed to reduce unwanted high frequency noise on the Ethernet Network connection in audio and video equipment and will work with both streaming services (Spotify, TIDAL, Qobuz, etc.) and locally stored music files.

CAD USB Control

The new CAD USB Control design resulted from our research and development of the CAD Ground Controls, 1543 MKII DAC and the many USB cables we have produced over the last 10 years. In our experience, reducing unwanted high frequency noise in audio systems significantly improves sound quality. The frequency of noise varies in every audio system and in each domestic environment – even the time of day on mains power. The USB Control reduces this unwanted high frequency noise across an extremely broad frequency spectrum, from KHz up into the GHz range. HiFi + Review

Connected Fidelity – RF Blocker

A wide-band radio frequency filter that increases audio fidelity. The connected-fidelity™ “RF Blocker” is a simple to fit radio frequency (RF) filter array. It is supplied in pairs and there are three connection options – banana and spade terminals, or bare wires. They simply fit across the loudspeaker + and - input terminals (or amplifier loudspeaker outputs).


The Furutech Flow-15 Plus Inline Power Filter effectively removes all of that high-frequency noise from the mains power before it reaches your components.

Furutech NCF Clear Line AC Optimiser

It takes just a moment to hear the difference that Furutech’s NCF Clear Line can make to your audio or video system. Why just a moment? Furutech’s Nano Crystal² Formula, also known as NCF, has resulted in a number of truly innovative and effective products over the past few years. NCF features a special crystalline material that has two distinct properties—it generates negative ions that eliminate static, and it converts thermal energy into far infrared. When combined with nano-sized ceramic particles and carbon powder, these crystals become the ultimate electrical and mechanical damping material. Created by Furutech, NCF is found exclusively in Furutech products and nowhere else. Now, Furutech has introduced perhaps the simplest way to implement NCF technology into your home—NCF Clear Line. Mono and Stereo Full Review Here

iFi Audio AC iPurifier – Mains Audio/Line Conditioner/Filter/Isolator/Purifier (Single Unit)

When you listen to music there’s a lot of background noise going on, coming in from the mains. Some noise cannot be missed but there’s also some that is not immediately obvious until it has gone. It comes from your power supply and interference and feedback from the power supply of other devices. Put the AC iPurifier in your set-up and you’ll notice the difference instantly.

MCRU Clip On Ferrite Cable Filters

  • Ferrite rings
  • Clip on design
  • 5,7,9.13 mm i.d
  • Price is for ONE piece

MCRU Exodus DC Blocker

The MCRU Exodus DC blocker plugs in between your mains block or mains conditioner to eradicate DC offset which is present in most household mains systems usually caused by the switch mode power supplies in your domestic equipment such as fridges and microwaves as well as any that are inside your hifi gear.

MCRU Mains Filtration Plug MKII

  • Suitable for use next to hi-fi and AV systems and we recommend using as many as practically possible due to the proliferation in RFI/EMI related issues in modern day hi-fi systems.