Hertz H8 DSP Review – Perfect Your Audio System “to the T” With This Processor

Those who have ever worked on upgrading their car’s sound system would know that a high-quality amplifier is a lifeline for your speaker and subwoofer.

It not only provides the control system for the speaker output, bass, distortion, and other aspects but also optimizes the performance of the equipment.

Hertz H8 DSP Review

While there are numerous options available for car audio processors in the market, it takes a lot of consideration to find the best fit for your preferences and system.

One of the most popular models is the Hertz H8 DSP that aims to transform the car’s audio system into something truly amazing.

In this review, we take a closer look at the product’s features and offerings and try to understand how it can help you upgrade your vehicle for better music experience.

What’s In The Box?

  • Hertz H8 DSP
  • Instruction Manual
  • Disc with Software
  • Input Harness
  • Programming cable (For Computer)

What Do You need for installation?

  • 12 AWG speaker wire for input to the H8 (This is our favorite)
  • Additional 12 AWG wiring for power and ground wiring.
  • 1 or more amplifiers (The Hertz H8 is a processor and needs an amplifier to operate properly).
  • A laptop style computer for programming.

Hertz is famous for its line of feature-packed amplifiers and speakers and has recently introduced a powerful digital signal processor to its collection of car audio upgrade solutions.

To serve the growing needs of music enthusiasts who want to make the most out of their car’s factory units, Hertz offers easy-to-integrate solutions.

The H8 DSP is a car audio processor designed to interface with analog and digital sources to transform any ordinary audio into a high-performance integrated system.

It is equipped with a complete suite of tuning tools for installation to make it easy to upgrade your audio system.


The Hertz H8 DSP comes with four speaker-level inputs that accept up to 15 volts of input. It also has a TOSLINK digital input and a pair of RCA auxiliary inputs that allows up to 5 volts.

For the output, it offers eight RCA outputs that deliver up to 4 volts of signal. The processor also comes with input level optimization LEDs to improve the system’s signal-to-noise ratio.

An amazing feature of the processor is the Universal Speakers Simulator technology. With this feature, the circuit delivers a suitable load to the factory radio so that you don’t need external load resistors for proper function.

Hertz H8 DSP Review

The H8 DSP also includes some outstanding hardware connections that make its usage extremely convenient. The first is the inclusion of sufficient memory for two calibrations.

Secondly, it offers external wire connections to allow users to switch quickly between the presets. The processor even features a remote detection system to allow it to activate itself automatically when the factory radio turns on. The availability of remote output means the device can turn on the amplifiers without intervention.

The software is developed to meet the ergonomics standard for the car audio industry and facilitates quick access to all the signal processing functions to give instant results and operational accuracy.

It has a simple and user-friendly design to allow making different adjustments to improve the experience in the car. The input/output configuration wizard makes the setup extremely simple.

Some of the operations the software allows performing include adjustment of delays to suit the listening position, parameters setting for input channels, and tuning of equalizers and crossovers for the channels.

Helpful Information

Hertz H8 DSP Review

Signal Processing

The processor software can be used in one of the two modes – Standard and Expert. In the Expert mode, the software allows configuration of any of the eight channels with low and high pass filters. Crossover points can be adjusted using 68 frequency options which is more than sufficient for a system.

Talking about the equalization, the processor has 31 bands with a standard spacing of 1/3octave. Each of the bands can be adjusted on 0.3dB steps up to +/- 12dB.

You also get a ‘select all’ function that allows you to change all the bands together. This feature proves to be useful if you need more than 12dB of boost or cut in any band.

The processor can calculate the delay for the outputs based on the distance between the speaker and the listening position provided.

You also get a fine-tune window to add details of delay in steps of 0.02 ms. Then, there is an ‘invert phase’ option for polarity adjustment control of each of the channels.

Each of the eight output channels can be adjusted from 0 to -40dB in steps of 0.5dB. The master volume control setting can be adjusted from 0 to -60dB in steps of 1dB and the master subwoofer control from 0 to -12 dB in steps of 0.5dB.

Hertz H8 DSP Review

Remote Control

The Hertz H8 DSP includes a DRC HE remote control which is compact and easy to use. It measures 2.48 x 1.4 inches and has five buttons with a small display.

Using this remote, you can control functions like master volume, balance and fader adjustment, and subwoofer level. It can also be used to toggle the presets and the source input.

It comes with a connection cable that is 4.5 meters long. The processor even includes a double-sided tape to surface-mount the remote in the vehicle.

The device can operate in a standalone mode with the remote control that works as the on/off switch. This means it doesn’t require a source unit in the audio system.

You can use the Bluetooth receiver to play music from your smartphone or use the TOSLINK connection to play with a media player.


Whether you are planning to build a car sound system or want to upgrade an existing one, a signal processor like the Hertz H8 DSP is certainly a great investment. It is a compact and straightforward device yet provides all the functions you need to make the most out of your audio system. With excellent hardware components and intuitive software, it gives users a simple way to improve the car environment.