Rockford Fosgate HRN-DSP-NI1 DSR1 Install T-Harness

The Rockford Fosgate HRN-DSP-NI1 is a vehicle-specific DSP installation T-harness for integrating a Rockford Fosgate DSR1 processor into select non-amplified Infiniti, Nissan, and Subaru factory audio systems. It connects at the factory head-unit harness, helping preserve the original vehicle wiring rather than requiring a conventional hardwired signal connection. The harness is intended to simplify the signal and speaker-wire connections needed when adding a compatible processor and aftermarket amplification.

This harness is for vehicle owners who want to upgrade a factory radio system while keeping the original radio in place. It is designed for select vehicles without a factory external amplifier, so fitment must be verified before purchase. The HRN-DSP-NI1 is not a head unit, amplifier, speaker, or DSP; it is the vehicle-side wiring interface for the installation.

Because it is a wiring harness, the HRN-DSP-NI1 does not add power, EQ, or a sound signature on its own. Its role is to provide organized access to factory audio wiring at the radio so a DSR1, DSP, line-output converter, or compatible amplifier can be connected appropriately. When used as intended, it supports a cleaner system layout and helps avoid unnecessary alteration of the vehicle's original harness.

The harness includes an 18-pin interface arrangement and loose speaker-wire leads identified with standard EIA speaker-wire colors. Those leads provide front and rear, left and right speaker-channel connections for system integration. A red/black lead supplies switched accessory output for turning on compatible amplifiers or DSP products when signal sensing is not being used.

Within a complete upgrade path, the HRN-DSP-NI1 works between the factory radio and the added audio equipment. It is designed for use with the Rockford Fosgate DSR1, which is required for a DSR1-specific installation and is sold separately. It may also be used for universal high-level input connections to a DSP, line-output converter, or amplifier when wired according to the applicable installation instructions.

Key Features

• Vehicle-Specific T-Harness: Connects at the factory radio harness in supported applications.
• Factory Wiring Retention: Helps retain the vehicle's original factory wiring integrity.
• DSR1 Integration: Designed for use with the Rockford Fosgate DSR1 processor.
• Speaker-Wire Breakout: Provides loose leads for factory speaker-wire integration.
• Switched Accessory Lead: Red/black lead can trigger compatible added audio equipment.
• Universal High-Level Capability: Can feed compatible DSP, LOC, or amplifier high-level inputs.

Design & Installation

The HRN-DSP-NI1 uses a purpose-built T-harness design with vehicle-side factory-style connections, an 18-pin interface plug, and labeled loose speaker leads. Manufacturer documentation identifies the speaker leads by standard EIA colors for straightforward channel identification. Rockford Fosgate does not publish conductor gauge or detailed material specifications for this harness.

Confirm vehicle fitment and verify that the vehicle does not use a factory external amplifier before installation. For DSR1 use, flash the DSR1 and follow the installation instructions supplied through the DSR1 software workflow; the DSR1 and aftermarket amplifier are sold separately. For universal high-level installations, the 18-pin plug may be removed and the identified speaker leads connected directly to the input wiring of the installed DSP, line-output converter, or amplifier.