The Sanctuary Perspective
The Radial Highline Stereo is a high-performance, 2-channel passive line isolator built to solve complex ground loop hum, buzz, and impedance matching issues between line-level audio equipment. Engineered specifically for demanding wet/dry/wet guitar rigs, multi-amp setups, pedalboard interfaces, and professional studio racks, the Highline provides complete galvanic isolation without altering your natural tone. Driven by two custom-wound Radial Eclipse transformers, it transparently handles massive signal levels from line-level preamp outputs, modeling processors, and audio interfaces with ruler-flat frequency response.
Product Intelligence & Signal Integrity Profile
- Best For: Complex Guitar Rig Interfaces (Wet/Dry/Wet), Pedalboard-to-FOH Routing, Stereo Modeler Outputs, Synthesizers, and Studio Line-Level Isolation.
- Sound Character: Completely transparent and uncolored with 10Hz to 40kHz linear bandwidth, zero active noise floor, and pristine phase response.
- Compared To: Offers higher signal handling headroom and wider frequency bandwidth than standard budget line isolators, utilizing high-grade Eclipse nickel-core transformers designed specifically for high-level line signals.
- Sanctuary Expert Note: "If you are running complex multi-amp setups, digital modelers, or stereo pedalboards into different power amps or FOH channels and hearing a high-pitched digital whine or 60-cycle ground hum, the Highline Stereo is the ultimate dead-silent fix."
Key Features & Engineering Highlights
- Dual Radial Eclipse Transformers: Custom-wound nickel-core transformers isolate audio channels to eliminate ground loops while delivering ruler-flat signal transfer from 10Hz to 40kHz.
- High Signal Handling & Low Distortion: Engineered to accept up to +22dBu input levels without saturation or phase distortion, making it ideal for hot line-level rig feeds.
- Independent Channel Ground Lifts: Dedicated ground lift switches for left and right channels immediately disconnect signal grounds to kill 60-cycle hum and buzz.
- Flexible I/O Connectivity: Features balanced ¼" TRS inputs and outputs alongside 3.5mm mini-stereo pass-through routing for seamless integration into pedalboards, rack drawers, or desktop setups.
- 14-Gauge Tour-Grade Construction: Built inside Radial's legendary "book-end" heavy-duty steel chassis with an I-beam internal structure that completely protects internal components from stage mechanical stress.
Technical Specifications
- Audio Circuit Type: Passive, Transformer-Coupled Line Isolator
- Number of Channels: 2 (Stereo or Dual Mono)
- Transformers: Dual Custom Radial Eclipse Nickel-Core
- Frequency Response: 10Hz – 40kHz (± 0.5dB)
- Dynamic Range: > 135dB
- Maximum Input Level: +22dBu @ 1kHz
- Total Harmonic Distortion (THD): 0.002% @ 1kHz (+4dBu)
- Input Impedance: 10kΩ Balanced / Unbalanced
- Output Impedance: 10kΩ Balanced / Unbalanced
- Inputs: 2 x 1/4" TRS, 1 x 3.5mm Stereo TRS
- Outputs: 2 x 1/4" TRS, 1 x 3.5mm Stereo TRS
- Switches: Ground Lift (CH 1 & CH 2)
- Power Requirement: None (100% Passive Operation)
- Chassis: 14-Gauge Steel Shell with Powder Coat Finish
Audio circuit type: Passive, transformer based
Transformer: JT-11-YMPC
Number of channels: Two channels (dual mono)
Frequency response: 20Hz ~ 20KHz (± 0.05dB)
Total harmonic distortion: <0.05% from 20Hz ~ 20kHz / -10dB, 0.0008 @1kHz / -10dB
Phase Deviation: ±0.3° from 20Hz ~ 20kHz / -10dB
Signal to Noise: 112dB
Features
Ground lift
Input Connectors: XLR Sum, Thru Sum
General
Construction: 14-gauge steel outer shell & 16-gauge chassis
Finish: Durable powder coat
Size (L x W x D): 5" x 3.3" x 1.8" (127mm x 84.1mm x 45.5mm)
Shipping size (L x W x D): 6.5" x 4" x 3" (165mm x 102mm x 76mm)
Power: Passive, no power required
Conditions: For use in dry locations only between 5°C and 40°C
Warranty: Radial 3-year, transferable
We are open Tuesday-Saturday from 10am until 6pm CDT.
Any order placed before 3pm CDT Tuesday through Saturday is processed for shipment the same day. Orders placed Sunday-Monday will be processed for shipment the following Tuesday.
For Free Shipping items, Effects pedals and small goods items are generally shipped via USPS Priority Mail, and Guitars and Amplifiers are generally shipped via UPS Ground.
Due to our central location in the middle of the US, most orders will be delivered within 1-3 days delivery time.
Other shipping methods are available (at an additional cost), including next day air.
Please call us directly at (972)540-6420 if you have any questions regarding shipping for your order.
