GND control.

Take out speaker hum.

Ground control to Major components.

The optimum configuration for each system is one Ground/Earth for the whole system. If a system has multiple Grounds/Earths, then it often creates unwanted ground loops. These systems will then have an annoying low-frequency hum (emitted from the speakers).

Current solutions either jeopardise (i) both safety and EMI shielding (e.g. cheater plug), or (ii) EMI shielding. And most are single country (US) uses only.

The GND Defender in the correct way, intelligently detects a ground loop and will cut the ground for that component.

AI ground detection.

With a GND Defender at the IEC power input, it will intelligently detect and remove the ground loop at the component.

Behind this, the GND Defender:

  • Intelligently breaks DC ground loops to eliminate ground loop hum
  • EMI shielding is retained
  • Equipment Safety is unaffected (not a ground lift – so maintains equipment safety ground)

If multiple ground loops exist, more than one GND Defender may be required.

The GND Defender is smarter than the average ground lift. By a long way.

GND Defender from iFi audio

Battleship build.

The GND Defender is not only at the cutting-edge in terms of technology but also safety:

  • High-performance glass passivated semiconductor
  • High Case Dielectric Strength of 1500VRMS UL Listed
  • X7R Capacitor
  • High-temperature stability
  • Flame resistant IEC socket/connector/chassis
  • Fireproof polymers UL94-V0

Remember that best practice is to always keep at least one direct power cable connection.

Power System Kit

Save money on your GND Defender by purchasing the new Power System Kit Bundle.

Cookie-Cutter ‘Sub-Sonic Filter’

Tom Evans who makes very nice phono stages made the following astute comment:

A rumble filter simply adds to the bass cut making your already “cut” records sound bass light. Plus, it “time-steps” the bass in relation to the higher frequencies (where our hearing is most sensitive) so much so it can confuse the ear into believing the bass is playing out of tempo.

iFi solution:

Since the very first iPHONO launched in 2012, we have used our own in-house ‘Subsonic Filter’. It made it into the iPHONO2 and the iPHONO3 and now, the ZEN Phono which is the very first time this filter is seen in such an affordable price level.

As there is only minimal vertical modulation remaining at very low frequencies with an an actual cut LP that is playable, we know that “vertical modulation” at low frequencies must be warp.

So we designed a filter to take advantage of this.

This is not artificial but real knowledge. By understanding fully how LPs are cut and replayed,  it is possible to filter record warp strongly without at the same time attenuating low bass or adding group delay.

EMI shielding is retained.

Surge overload rating of 220A. With a maximum rating >10A, continuous current rating 7A, it handles all voltages around the world from 90-240V.


Sambs Hifi


WOD Audio

Nidderau (Germany)

die Kopfhörerboutique


This product is currently out of stock and unavailable.

AI Ground DetectionEach unit will automatically disconnect the ground on that device
Ground SafeAuto reinstatement of ground connection to pass current if a fault is detected
Voltage rating90 – 240 volts
Surge overload rating220A
Continuous current rating10A (1100W – 2400W)
Universal IECHospital-grade IEC connectors
Dimensions68 x 37 x 32 mm / 2.7” x 1.5” x 1.3”
Weight61g / 2.2oz

GND Defender “…does what it says on the tin…”

Thanks to HiFi Choice for recommending our GND Defender!

“The GND Defender definitely does what it says on the tin and solves the problem of earth loop hum in a safe and elegant way.”

Hi-Fi Choice

(Click name to read original review)

Simple and Effective!

Multiple grounds in my system caused this low frequency hum, I did some research and found this was in fact a ground loop. The GND Defender worked its magic and removed this hum- really pleased!


(Click name to read original review)

Great product – it solved a back to earth brilliantly

Produced perfectly in line with expectations, it solved a ground loop that was affecting my sub very well. I had already tried to solve differently but without success, with this simple device the problem is gone.


(Click name to read original review)

IFI DC Blocker and GND Defender – A Practical Solution to Power Problems – Review

“IFI’s DC Blocker and GND Defender are two products that take care of the point and solve two problems present in many plants in a direct and immediate way. The cost is not very low, but both work very well and put an end to power problems difficult to solve and in my case they immediately eliminated the vibrations of the power amp, a problem that I had been carrying around for a long time, therefore, I found the money spent on the DC blocker the 150 euros best invested in my systems since the buzz was very annoying.”
Read the full review here…


(Click name to read original review)

Best solution for ground loop problem!

Good job ifi audio! It really works for my system! Eliminate the ground noise and smart design!


(Click name to read original review)