Hall Technologies GLI-35MM Stereo Audio Ground-Loop Isolator - Clean

In this review of the Hall Technologies GLI-35MM the bottom line is simple: if you need to remove audible hum or buzz between a source device and a TV or amplifier, this small inline unit does the job with minimal fuss. The GLI-35MM is aimed at AV professionals and anyone running presentations or connecting notebooks, desktops, or portable players to sound systems where ground loop interference appears. It earns its place by delivering reliable isolation and a near-flat frequency response, so the audio character remains intact while unwanted noise disappears.

Key Features

• Ground-loop elimination: Removes hum and buzz between an audio source and TV or amp so presentations and music play cleanly without background interference.
• Universal 3.5mm compatibility: Works with notebook and desktop PCs and all portable devices that use a 3.5mm mini-stereo plug, making it simple to add to existing cables.
• Near-perfect frequency response: Maintains audio fidelity with a quoted response of +.03 dB from 20 to 20,000 Hz so lows and highs remain natural.
• Proprietary transformers and filters: Uses designed audio transformers and filtering to eliminate spurious buzz and hum without audible side effects.
• Compact and economical: Small inline form factor is easy to pack for classroom, conference, or mobile AV setups while keeping costs low.

Who It's For

The GLI-35MM is best for AV technicians, educators, presenters, and homeowners who frequently connect laptops, phones, or other 3.5mm-equipped devices to TVs, projectors with external speakers, or amplifiers and need a quick fix for ground loop noise. It is particularly useful in classrooms, conference rooms, and small installations where a noisy ground connection would otherwise disrupt speech or music.

Those who should look elsewhere include users needing balanced XLR isolation for pro audio racks or installations requiring gain control, multiple channels, or DSP features; the GLI-35MM is a simple single-channel isolator and not a multichannel processor.

Pros & Cons

Pros

• Effectively eliminates audible hum and ground loop buzz in consumer and PC-to-AV connections.
• Maintains a near-flat frequency response, preserving tonal accuracy from 20 to 20,000 Hz.
• Plug-and-play 3.5mm design is universally compatible with portable devices and computers.
• Compact, inexpensive solution that is easy to deploy in classrooms and conference rooms.

Cons

• Limited to single-channel stereo via 3.5mm; not suitable for balanced pro audio I/O or multichannel installations.
• No built-in level control or additional signal processing features for advanced audio work.

Specifications

Product	GLI-35MM Stereo Audio Ground-Loop Isolator & Filter
Connectors	3.5mm mini-stereo plug and jack
Frequency response	+.03 dB from 20 to 20,000 Hz
Primary function	Eliminates ground loop noise between source and audio equipment
Construction	Proprietary audio transformers and filters
Use cases	Notebooks, desktops, portable devices to TV or amplifier connections
Size	Compact inline form factor

Our Verdict

The Hall Technologies GLI-35MM is a practical, low-cost fix for common ground loop problems when connecting consumer devices to TVs and amplifiers. It delivers clean audio with minimal impact on tonal balance and is ideal for classrooms, conference rooms, and mobile AV setups. Buy it if you need a simple, reliable isolator; audio professionals requiring balanced multichannel solutions should consider more advanced hardware.

Frequently Asked Questions

Will this remove all hum from my system?
It removes hum caused by ground loops between the source and the receiving device in most consumer setups, but it cannot fix issues unrelated to grounding or faults in equipment.

Can I use it with phones and tablets?
Yes, the 3.5mm mini-stereo connector works with any portable device that provides a standard 3.5mm audio output.

Is it suitable for pro audio racks?
No, it is a single inline stereo isolator and is not intended as a replacement for balanced XLR isolation or multichannel professional audio gear.