The Tannoy CMS 1201 BACKCAN is a dedicated acoustic and structural enclosure designed as a critical accessory for the CMS 1201 series of in-ceiling loudspeakers. Its primary role is to provide a sealed, rigid rear chamber when these speakers are installed in environments with open ceiling plenums, such as those found in commercial offices, retail stores, and modern residential constructions. By enclosing the back of the loudspeaker, this can effectively isolates the driver's rear sound waves from the open, often insulated space above the ceiling. This isolation is essential for preserving the speaker's designed bass response and overall acoustic performance, preventing sound energy loss and phase cancellation that can severely degrade audio clarity and impact. The sealed environment also acts as a protective barrier, shielding the speaker's internal components from dust, moisture, and debris commonly found in plenum spaces.

Constructed from high-grade, fire-retardant materials, the BACKCAN plays a vital role in supporting and maintaining the fire rating integrity of the ceiling assembly. In many commercial building codes, maintaining fire barriers between spaces is mandatory, and this accessory helps ensure the loudspeaker installation does not compromise that safety system. The cylinder is engineered for straightforward integration, featuring a secure twist-and-lock mechanism that allows it to be quickly and reliably attached to the matching CMS 1201 loudspeaker chassis after it is mounted in the cut-out. This creates a unified, robust assembly that is both acoustically optimized and mechanically stable.

The design includes pre-formed knock-outs for neat cable entry, facilitating a clean and professional installation. For audio consultants and system integrators, the CMS 1201 BACKCAN is not an optional extra but a fundamental component for achieving reference-grade performance from the CMS 1201 loudspeaker series. It ensures that the speaker performs precisely as engineered by the manufacturer, delivering consistent, full-range sound in demanding distributed audio applications where performance, reliability, and compliance are non-negotiable.