iFi iDefender Max - USB-C Ground Loop Breaker

The SilentPower iDefender Max is an intelligent USB-C ground loop breaker designed to eliminate distracting hum and noise in computer-based audio systems. When multiple devices and power plugs create excess earth connections, ground loop noise can creep into your signal chain and show up as an annoying low-frequency buzz in speakers or headphones. iDefender Max intelligently removes unwanted earth connections to restore clean, quiet playback—so your USB audio sounds the way it should.

Built with SilentPower’s IsoGround® Technology, iDefender Max breaks ground-loop interference without compromising safety. Unlike basic “ground lift” solutions, it can automatically reestablish the earth connection if a current-related fault is detected, helping ensure excess current is directed to earth rather than your connected gear. It also includes USB Noise Termination® to reduce noise from USB power at the source, plus a dedicated external USB-C power input that bypasses USB power from the computer—letting you upgrade performance further with a cleaner external supply.

Whether you’re running a USB DAC, headphone amp, powered speakers, or a broader USB-C setup, iDefender Max supports up to 100W (20V/5A) and maintains USB 3.0 compatibility (with backward compatibility to USB 2.0), helping preserve high-speed data transfer and reliable high-resolution playback.

What It's Good At:

• Eliminating ground loop hum/buzz in USB-C computer audio setups for quieter listening
• Intelligently lifting unwanted earth connections while maintaining user and equipment safety
• Reducing USB power noise at the input for cleaner, more “black background” playback
• Enabling higher-performance setups via external USB-C power input (bypass noisy PC USB power)
• Supporting up to 100W (20V/5A), expanding compatibility beyond typical USB DAC use
• Preserving USB 3.0 data performance (with USB 2.0 backward compatibility) for stable playback

iFi iDefender Max Full Specifications:

• Product Name: iDefender Max
• SKU: 03-20-002-0001-00
• Type: Intelligent USB-C ground loop breaker
• Key Technologies/Functions:
  • IsoGround® Technology (intelligently removes earth connection without compromising safety)
  • USB Noise Termination® (removes noise from USB power at the source)
  • External USB-C Power Input (bypasses USB power from the connected PC; supports clean external supply use)
  • Safety Function: Automatically reestablishes earth connection when a current-related fault is detected
• Input/Output: USB-C
• Compatibility: USB 3.0 (backwards compatible with USB 2.0)
• Max Power Support: Up to 100W (20V/5A)
• Dimensions: 51.3 × 20 × 12 mm (2.0 × 0.8 × 0.5”)
• Net Weight: 21 g (0.74 oz)
• Limited Warranty: 12 months
• What’s in the Box:
  • 1 × iDefender Max
  • 1 × Instruction Card
• Note: The image colour may differ from the actual product due to lighting. Please refer to the product for accuracy.

iFi iDefender Max Q&A:

What does the iDefender Max do in an audio setup?

It breaks USB-C ground loops that commonly cause hum or buzz in computer-based audio systems, helping restore quieter, cleaner playback.

How do you connect the iDefender Max?

Place it inline between your computer and your USB device—connect it between the USB-C source and the USB device to help eliminate ground-loop noise.

Will it affect USB audio quality or high-resolution playback?

It’s designed to maintain USB data performance while reducing noise and ground-loop interference, supporting USB 3.0 with backward compatibility to USB 2.0.

Is the iDefender Max safe compared to basic ground-lift adapters?

Yes—its design is intended to avoid compromising safety by automatically reestablishing the earth connection if a current-related fault is detected.

Do I need an external power supply to use it?

No—external USB-C power is optional. The external USB-C power input is there if you want to bypass USB power from the PC and use a cleaner supply.

What kinds of devices can it work with?

It’s built for USB-C connections and supports up to 100W (20V/5A), making it compatible with a wide range of USB-C devices and not limited to only USB DAC use.

What is USB Noise Termination® used for?

It helps remove noise riding on USB power right at the source, reducing the chance of power-related noise bleeding into your audio chain.

What warranty coverage comes with the iDefender Max?

It includes a 12-month limited warranty.