Pricing and availability

We compare 600+ stores and found this item at 8 stores. Prices updated .

Sweetwater
5.0 (4)
$249.99
Amazon
4.8 (10)
$249.99
B&H
5.0 (1)
$249.99
Thomann
5.0 (1)
$321.00 $319.00 $2.00 · All time low

Average Price: $259

Standard/Professional

$119

$300+

Price Tier

Budget

Standard

High-end

Price History

Based on price data from 7 merchants for "Radial Highline Stereo Passive Line Isolator". Prices shown reflect NEW condition. Tracking began Apr 2, 2026.

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Description

In the dynamic world of studio recording, the Radial Highline Stereo Passive Line Isolator emerges as a steadfast companion for musicians and audio engineers alike. Designed to tackle the intricate challenges posed by amp simulators and modelers, this compact yet powerful tool is your ultimate ally in maintaining pristine signal quality. At the heart of the Highline Stereo are the premium Jensen 1:1 transformers, renowned for their ability to preserve the full volume of your signal while ensuring complete isolation from noise-inducing ground loops.

Whether you're running long cable distances or interfacing with a complex PA system, this isolator effortlessly converts unbalanced line-outs to balanced signals, warding off signal degradation. Its stereo inputs and outputs provide versatility, allowing for multiple rig connections, signal splitting, or even summing stereo inputs to mono via its innovative sum feature. The inclusion of a ground-lift switch further enhances its noise-reducing capabilities, making it an indispensable tool for any professional audio setup.

Key Features:

  • Converts unbalanced line-out to balanced, preventing signal degradation
  • Jensen 1:1 transformers for superior signal isolation and integrity
  • Breaks up ground loops and protects against phantom power
  • Stereo I/O for additional lines or signal splitting
  • Sum feature turns input and thru jacks into a passive mixer, converting stereo sources into mono
  • Ground-lift switch to eliminate unwanted noise

Product specs

Type Guitar Simulaton Stereo Direct Box
Channels 2
Ground Lift Yes
Inputs 2 x 1/4" (L/R input)
Outputs 2 x 1/4" (L/R Thru), 2 x XLR (L/R balanced out)

FAQs

What is the primary function of the Radial Highline Stereo Passive Line Isolator?

The Radial Highline Stereo Passive Line Isolator is designed to eliminate ground loop hum and buzzing by isolating guitar amp simulations from the PA system, ensuring a clean and noise-free audio signal.

Does the Radial Highline Stereo Passive Line Isolator require a power supply?

No, the Radial Highline Stereo Passive Line Isolator is a passive device and does not require any external power supply to function.

What types of connections does the Radial Highline Stereo Passive Line Isolator support?

The Radial Highline Stereo Passive Line Isolator features 1/4" inputs and thru outputs for amp monitoring, along with balanced XLR outputs for connecting to a PA system.

How does the ground lift switch on the Radial Highline Stereo Passive Line Isolator work?

The ground lift switch on the Radial Highline Stereo Passive Line Isolator helps eliminate unwanted buzz by disconnecting the ground path between connected devices, reducing the potential for ground loop noise.

Can the Radial Highline Stereo Passive Line Isolator handle high-output signals?

Yes, the Radial Highline Stereo Passive Line Isolator uses Jensen transformers to maintain full signal level and tone from amp simulations, making it suitable for high-output signals without signal degradation.

Radial Engineering

Radial Engineering

Highline and Highline Stereo Amp Sim Passive Line Isolators

Video thumbnail for Highline and Highline Stereo Amp Sim Passive Line Isolators by Radial Engineering

Highline and Highline Stereo Amp Sim Passive Line Isolators

Radial Engineering

Radial Engineering

Video thumbnail for NAMM 2025 - Radial Engineering Full Booth Tour by Radial Engineering

NAMM 2025 - Radial Engineering Full Booth Tour

Radial Engineering

Radial Engineering

Video thumbnail for Radial Engineering Highline & Highline Stereo NAMM 2025 by Premier Guitar

Radial Engineering Highline & Highline Stereo NAMM 2025

Premier Guitar

Premier Guitar

Reviews

Owner Insights

We analyzed real musician discussions from forums and Reddit to find what players love, question, and tweak about Radial Highline Stereo Passive Line Isolator.

Features and functionality

  • The Radial TWIN ISO Passive Line-Level Isolator maintains line level integrity while isolating ground and ensuring balanced lines, ideal for complex PA setups.

    Source

User experience

  • Owners using the Radial Twin-Iso highlight its robustness compared to smaller alternatives like ISO-BLOX, which are better for occasional use.

    Source

Use cases and applications

  • Proco IT4A 4-channel line isolator is recommended for rack integration, providing seamless interfacing with different power-sourced systems in venue setups.

    Source

Setup and maintenance

  • Lifting the shield on XLR cables at secondary input zones can effectively address ground loops without affecting signal levels.

    Source

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Artist usage

Add artist
See how Daniel Donato uses Radial Highline Stereo Passive Line Isolator

Daniel Donato

Guitarist

Daniel Donato's Cosmic Country

...
Verified via YouTube

In the "Daniel Donato Rig Rundown" video by Premier Guitar, Daniel Donato is shown using a Radial Highline Stereo Passive Line Isolator, which can be observed connected to the Fender Tone Master Pro at the 12:08 mark.

Album Usage

The Radial Highline Stereo Passive Line Isolator has been featured on the following albums:

Genre Usage

Based on how artists on Equipboard use this gear, it is most commonly found in the following genres.

Used With

Based on how musicians on Equipboard use Radial Highline Stereo Passive Line Isolator, it is most commonly used with the following gear.

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