Rebec RPX-B680V2 – 6-Channel DSP Amplifier with Flexible 8-Channel Processing

Product Overview

The Rebec RPX-B680V2 is a compact DSP amplifier from Rebec’s RPX-B Series, combining digital signal processing with six channels of Class AB amplification and eight channels of low-level output.

Compared with a conventional four-channel DSP amplifier, the six amplified channels provide greater flexibility for building multi-way car audio systems without immediately requiring additional external amplification.

The RPX-B680V2 supports factory high-level integration, low-level analog input, USB Audio, Optical, Coaxial and Bluetooth sources. Together with PC/App tuning and eight processed low-level outputs, it can be used both as an integrated DSP amplifier and as the processing center of an expandable audio system.

Six-Channel Class AB Amplification

The Rebec RPX-B680V2 uses a Class AB amplifier topology with six built-in amplified channels.

At 14.4V and 4Ω, channels 1–4 provide 25W RMS per channel, while channels 5–6 provide 20W RMS per channel, measured at 1% THD.

At 3Ω, output increases to 33W RMS × 4CH + 27W RMS × 2CH.

The six-channel architecture provides two additional amplified channels compared with a conventional four-channel layout, allowing more loudspeaker sections to be driven directly from the DSP amplifier.

This makes the RPX-B680V2 suitable for configurations such as a 2-way active front stage combined with a passive rear speaker system, or a 3-way active front stage, depending on the actual system design.

8-Channel Output for Further Expansion

Although six amplifier channels are integrated into the unit, DSP system capability extends beyond those internal outputs.

The Rebec RPX-B680V2 provides eight low-level outputs at 2.35V, allowing processed signals to be sent to external power amplifiers.

This gives the system designer the option to use the six internal amplifier channels for selected loudspeakers while reserving other processed channels for external amplification.

For example, a system can use the integrated amplifier for the main speaker channels while adding a separate amplifier for a subwoofer or another speaker section.

The RPX-B680V2 can therefore remain at the center of the system even when the installation is expanded beyond its built-in amplification.

AP5688 DSP Processing Platform

The updated Rebec RPX-B680V2 uses the AP5688 DSP chipset, together with a CJC4344 DAC and ES7210 ADC.

DSP processing operates at a 48kHz sampling frequency.

The system provides a 31-band EQ for detailed frequency adjustment, while the crossover section supports Butterworth, Linkwitz and Bessel filter types.

Up to six presets can be saved and recalled, allowing different tuning configurations to be stored within the processor.

System tuning can be performed through PC or App, giving installers direct access to the DSP configuration environment.

The factory documentation also specifies that the updated PC-tuning software provides expanded functionality compared with the RPX-B680 model.

Multiple Source Integration Options

The Rebec RPX-B680V2 provides several analog and digital input options for integration with different car audio sources.

For factory audio integration, it provides four high-level inputs supporting 7.9–24.9Vpp.

For low-level analog sources, two input channels support 1.3–5.1Vpp.

Digital sources can be connected through Optical (Toslink) or Coaxial, both supporting signals up to 96kHz/24-bit.

The RPX-B680V2 also provides USB Audio input and built-in Bluetooth 5.2, adding direct digital and wireless source options to the system.

This combination allows the unit to work with factory audio sources as well as a variety of external playback devices.

Signal Performance

The Rebec RPX-B680V2 has a specified frequency response of 20Hz–20kHz, a dynamic range of 93dB, and a signal-to-noise ratio of 105dB.

Total harmonic distortion is specified at below 0.01% for low-level signals and below 0.03% for high-level signals.

According to the product information, the sound-performance objective of the RPX-B680V2 focuses on high resolution, accurate computer-based tuning and accurate music reproduction.

Compact Integrated Design

Despite combining DSP processing with six amplifier channels, the Rebec RPX-B680V2 maintains compact dimensions of approximately 120 × 167 × 43 mm.

Its operating voltage range is 10–16V, with a standby current of 440mA and maximum current of 25A.

This compact architecture allows signal processing and six-channel amplification to be installed as a single component, reducing the need for multiple separate devices in systems where the internal amplifier provides sufficient channel capacity.

At the same time, the eight low-level outputs ensure that the system is not restricted to the six integrated amplifier channels.

More Channels, More System Flexibility

The defining advantage of the Rebec RPX-B680V2 is the combination of six-channel Class AB amplification and eight-channel DSP output within a compact platform.

The six built-in amplifier channels provide additional flexibility for active speaker configurations, including a 3-way active front stage, while the eight low-level outputs allow external amplifiers to be incorporated when additional power or channels are required.

Combined with the AP5688 DSP, 31-band EQ, Butterworth/Linkwitz/Bessel crossover options, six presets, PC/App tuning, USB Audio, 96kHz/24-bit Optical and Coaxial inputs, and Bluetooth 5.2, the RPX-B680V2 provides a practical foundation for both straightforward and expandable DSP-based car audio systems.

Rebec RPX-B680V2

6-Channel Class AB DSP Amplification with 8-Channel Processing for Flexible Active Car Audio System Configuration.