250m Loop Amplifier

The Opus Single-Channel Class D Induction Loop Amplifier LD1.0 provides assisted listening for rooms with a single loop installation. Designed for permanent use in medium-sized spaces, it delivers audio to compatible telecoil-equipped hearing aids and is suitable for applications such as meeting rooms, lecture spaces and places of worship.

Opus specifies indicative coverage of up to 250 m², subject to room geometry, listening height and surrounding metal. The amplifier delivers 5A RMS output current at 1kHz and supports loop impedances from 0.5 to 3Ω. A SmartLoop design study is recommended to establish the appropriate cable layout and assess coverage before installation.

Three audio inputs provide flexibility when connecting microphones and existing sound equipment. Two inputs are switchable between line and microphone operation, while a dedicated priority 100V input supports connection to a suitable public address system. A 12V / 2mA phantom supply is available for compatible microphones.

The LD1.0 incorporates compression and automatic gain control to help manage variations in source level. Adjustable metal loss correction from 0 to 3dB per octave allows installers to compensate for the effects of nearby metal on the loop’s audio performance.

Continuous monitoring checks the amplifier and loop, with front-panel indicators showing power, protection, clipping and loop status. An NO/NC fault relay provides a contact output for external fault monitoring, helping maintenance teams identify issues without relying solely on a local visual check.

An integrated 115/230V AC, 50/60Hz power supply supports fixed installation. The compact enclosure measures 42 × 200 × 215 mm and weighs 1.48kg. Final commissioning should verify loop performance throughout the intended listening area, taking account of the room’s installation constraints.