Hertz S8 DSP 8-Channel Digital Signal Processor

The Hertz S8 DSP is an ultra-compact digital signal processor designed to integrate factory or aftermarket audio sources into a more precisely tuned sound system. It accepts low-level RCA signals, amplified speaker-level signals, or a coaxial S/PDIF digital source, then provides eight RCA preamp outputs for external amplifiers. This makes it a practical interface for active speaker systems, multi-amplifier upgrades, and OEM-audio retention projects.

Built for cars, motorcycles, and free-placement applications such as boats, vans, or pickups, the S8 DSP gives an installer flexible signal routing without requiring a large processor chassis. Its six analog input channels can be configured for either preamp-level or speaker-level signals, while the coaxial digital input supports PCM audio up to 24-bit/96 kHz. The processor is intended to sit between the source unit and system amplifiers rather than power speakers directly.

The 32-bit DSP platform processes audio at 96 kHz/24-bit resolution and is Hi-Res certified by the Japan Audio Society. Each input channel provides a 7-band parametric equalizer to help correct the tonal shaping commonly present in OEM systems. Each of the eight output channels adds independent level control, 15-band parametric EQ, crossover filtering, polarity control, and time alignment.

Its crossover tools support full-range, high-pass, low-pass, and band-pass operation with Butterworth, Bessel, and Linkwitz-Riley filter options. Adjustable delay helps align speaker arrival times at the listening position, while the selectable output signal limiter is designed to help prevent output clipping. Four stored presets allow different system tunings to be recalled through software or external control wiring.

The S8 DSP is configured from Windows or macOS software, or from compatible Android and iOS devices through Bluetooth 5.0 BLE. Bluetooth is used for control, setup sharing, and DRC-style adjustment rather than music streaming. With all connections arranged on one side and the required harnesses supplied, it is well suited to compact installations where organized wiring and detailed tuning are priorities.

Key Features

• Six Analog Inputs: Accepts either low-level preamp signals or amplified speaker-level signals for OEM and aftermarket source integration.
• Coaxial Digital Input: Supports PCM S/PDIF input up to 24-bit/96 kHz from a compatible digital source.
• Eight RCA Outputs: Provides eight 4 Vrms-capable preamp outputs for connection to external amplifiers.
• Per-Channel Tuning: Each output channel includes level, 15-band parametric EQ, crossover, delay, and polarity adjustment.
• USS OEM Integration: Universal Speakers Simulator technology supports connection to certain factory radios with speaker-load sensing.
• Bluetooth 5.0 Control: Configure and operate DSP functions from compatible mobile devices, PC, or Mac.

Design & Installation

The S8 DSP uses a compact enclosure made from metal and composite materials, with an anti-corrosion-treated circuit board for applications exposed to more demanding environments. Its connectors are grouped on one side to simplify cable routing and service access. Status and Bluetooth LEDs provide visual indication of operating, connection, clipping, digital-input, and update conditions.

Install the processor between the source unit and external amplifiers, using the included input, output, power/remote, and speaker-input harnesses as appropriate for the system. Use the low-level inputs for RCA-equipped sources, the high-level inputs for factory amplified outputs, or the S/PDIF input for a compatible PCM digital source. Final setup requires the Hertz software or compatible control app and should include proper gain, crossover, EQ, routing, and time-alignment adjustment for the connected speakers and amplifiers.