Amina MOBIUS5I Invisible Loudspeaker

Amina Mobius5i Invisible Loudspeaker – Plaster-In Panel Speaker for Walls and Ceilings

The Amina Mobius5i is a passive invisible loudspeaker that disappears completely into a wall or ceiling. Instead of a conventional cone and grille, it uses a flat vibrational panel driven by exciters, and once the panel is installed it is covered with a 2 mm skim of plaster or another approved decorative finish. The wall itself becomes the radiating surface, so the room keeps its clean lines with no visible speaker, no grille and no shadow gap where the sound is coming from.

Mobius is Amina’s fully covered loudspeaker range, designed for in-wall and in-ceiling use in stud or solid constructions, and also for integration into cabinetry and millwork. The Mobius5i is the mid-power model in the range, rated at 50 W continuous, and it suits residential distributed audio, multichannel surround systems and high-end commercial spaces where the interior design cannot be interrupted by visible hardware.

Key features

• Fully invisible once covered with a 2 mm plaster skim or approved surface material
• 50 W continuous and 100 W peak power handling
• 180 x 180 degree dispersion at all frequencies for a very wide listening area
• OptiDrive, OptiDamping and Reduced Resonance Exciter technology
• Second-generation Excelsior class high-frequency transducer on a honeycomb aluminium soundboard
• Lightweight panel at 1.4 kg, 33 mm deep, for cavity or solid wall installation
• Designed to work with Amina inline or rack-mount protection units

How an invisible panel speaker works

A conventional loudspeaker pushes air with a piston-like cone, which concentrates sound in a beam in front of the cabinet. The Mobius5i works differently. Its exciters vibrate a rigid, lightweight panel in a controlled pattern of bending modes, turning a large surface area into the sound source. Because the radiating area is large and the vibration is distributed, the panel produces the exceptionally wide 180 degree dispersion Amina specifies, filling a room evenly rather than creating one narrow sweet spot. Voices stay clear across a broad seating area, and background music remains consistent as listeners move around the space.

Performance, in the manufacturer’s figures

With the specified 2 mm plaster covering in place, Amina rates the Mobius5i at 86 dB SPL sensitivity at 1 metre for a 2.83 Vrms input, with a frequency response of 75 Hz to 29 kHz at -6 dB. Nominal impedance is 4 ohms. The updated high-frequency transducer extends response smoothly into the ultrasonic region and improves midrange sensitivity compared with the previous Mobius generation, while OptiDamping controls panel resonances to keep bass definition tidy at higher levels. Deep bass below the panel’s natural range is normally handled by a separate discreet subwoofer in a complete system design.

Installation and protection

The panel measures 450 x 345 x 33 mm and is fixed using Amina’s CV345 cavity backbox or SW345 solid-wall backbox, or with mounting blocks. Coverings are not limited to plaster: the Mobius range can be finished under wood, leather, natural or manufactured veneers and laminates, and other approved materials, which makes it workable in joinery, media walls and feature ceilings as well as plain plastered surfaces. Amina specifies a protection unit in the feed to each panel, either the inline APUi50C_2 or a rack-mount APU-RS8iC or APU-RS16iC unit, to guard the exciters against overload in daily use. Installation and finishing should be carried out by an installer familiar with the system, and the panel should be tested before the finish is applied.

Where it fits

The Mobius5i is a considered choice for design-led homes, apartments where visible speakers are unwelcome, hospitality and retail interiors, boardrooms and places of worship that need clear speech and music without visual clutter. It is a passive loudspeaker, so it needs a suitable external amplifier matched to its 4 ohm impedance and 50 W rating, and it rewards being planned as part of a whole system: amplifier, protection, panel positions and, where the programme demands it, discreet bass support.

For rooms that must look untouched while sounding properly engineered, the Mobius5i offers a rare combination: genuine architectural invisibility, wide and even coverage, and the output to serve as the main speaker in a serious distributed or surround installation.