Amina Backbox CV345 For Compatible Invisible Speakers

Amina Backbox CV345

The Amina Backbox CV345 is a cavity backbox for Amina invisible loudspeakers with 450 x 345 mm panels, including the Edge5i, Edge7i, Mobius5i, Mobius7i and MobiusDual, and the Sapphire models that use CV345 mounting. Invisible speakers radiate sound through the plastered wall or ceiling surface itself, and what sits behind that surface shapes how they perform. The CV345 creates an acoustically tuned, consistent cavity behind the speaker, so every installation behaves the same way, and it reduces the airborne sound travelling rearward into the room behind. It is an installation accessory, fitted into plasterboard cavity walls and ceilings before the speaker is plastered in.

Key features

• For Amina invisible speakers with 450 x 345 mm panels
• Acoustically tuned, consistent rear cavity
• Average 26 dB reduction in rearward airborne sound, 150 Hz to 5 kHz
• Fully recyclable aluminium enclosure
• Dimensions 500 x 352 x 73 mm, weight 2.8 kg
• Minimum cavity depth 75 mm
• Designed for retrofit into 12.5 mm plasterboard
• Cable entry via rubber grommet, replaceable with an M20 gland

Why a backbox matters

An invisible loudspeaker uses the wall surface as its radiating panel, driven from behind. Without a defined enclosure, the cavity behind each speaker differs with stud spacing, insulation and services, and performance varies from room to room. The CV345 fixes the air volume and shape behind the panel, giving the installer a known acoustic environment and the listener consistent results across every speaker in the project. It also provides a solid mounting platform that holds the speaker in correct alignment while the plaster skim is applied, which is critical because alignment at this stage decides the finished surface quality.

Keeping sound in the room

Sound that escapes rearward into a cavity can be heard clearly in the room behind, a real problem for bedrooms above living spaces and for partition walls between dwellings. Amina rates the CV345 at an average 26 dB reduction in airborne sound transmission over the 150 Hz to 5 kHz range when used with a compatible invisible speaker. That does not stop mechanically transmitted noise through the building structure, and Amina recommends additional measures for speakers in partition walls or backing onto occupied rooms, but for most cavity walls and ceilings the backbox is the simplest effective step.

Installation notes

The backbox is designed to be retrofitted into 12.5 mm plasterboard, requiring a cutout of about 455 x 350 mm and a minimum cavity depth of 75 mm. It should make contact only with the rear of the plasterboard and not touch the stud framework, which limits mechanical noise transmission into the structure. Speaker fixing uses four self-tapping flange-head screws and wall fixing eight self-tapping drywall screws, both supplied. Cable enters through a rubber grommet that can be replaced by an M20 gland. For board thicknesses other than 12.5 mm, Amina’s shim kits and installation manual cover double-skinned and alternative constructions.

Compatibility and planning

Backboxes are model specific, so selection starts with the speaker. The CV345 matches the 450 x 345 mm panel format; smaller Amina speakers use different backbox sizes and are not interchangeable. Confirm the exact speaker model, board thickness and cavity depth at design stage, before plaster work begins, because retrofitting the correct box after finishing is disruptive. The enclosure is formed from fully recyclable aluminium and weighs 2.8 kg.

For any Amina invisible speaker installation in a cavity wall or ceiling, the Backbox CV345 is the component that makes the result predictable: a tuned cavity, correct alignment for plastering, and a meaningful reduction in sound leaking to the room behind.