The Bose Professional CSP-428 commercial sound processor is designed to deliver intelligent, balanced audio performance for a wide range of business environments. Featuring AutoVolume technology, it continuously adjusts music levels in real time to match ambient noise when paired with AVM-1 sense microphones (sold separately), ensuring consistent sound throughout the day. SmartBass technology provides rich, controlled low frequencies that adapt to room acoustics and listening sensitivity, delivering noticeable yet never overpowering bass—even at lower volumes. Opti-Source Level Management eliminates uneven volume between up to four input sources, while Opti-Voice ensures smooth transitions between background music and announcements.

With full mixing functionality, input sources can be blended and assigned to different listening areas, and the system can be zoned into up to five distinct areas for tailored audio control. Each zone can be managed using optional wall-mounted ControlCenter controllers or the ControlSpace Remote app for convenient user operation. The CSP-428 also supports pre-configuration through the CSP Configuration Utility app, allowing installers to export and upload settings efficiently.

Built for cost-effective commercial installations, the processor offers 2 × 2 balanced analog I/O, mono-summed RCA inputs, multiple control inputs and outputs, Ethernet connectivity, mute contact, and Bose Professional AmpLink for simplified digital audio connection to compatible amplifiers—reducing wiring complexity and potential failure points. Its network-based architecture supports Cat-5/Cat-6 wiring with PoE capability, as well as both DHCP and static IP configurations for flexible and scalable system design.

Ideal for retail stores, restaurants, bars and pubs, hospitality spaces, fitness centers, and office environments, the CSP-428 provides reliable performance and professional-grade sound management tailored to commercial applications.