2 x 15A Dual Channel Loop Amplifier

The Opus Two-Channel Class D Induction Loop Amplifier LD4.2 provides assisted listening for large venues, delivering up to 2 × 15A RMS output current. Designed for permanent installations, it supports compatible telecoil-equipped hearing aids in applications such as auditoriums, conference centres, lecture theatres and places of worship.

Its two loop outputs use Neutrik NL4 speakON connectors, providing dedicated connections for the installed loop cabling. The amplifier offers a frequency range of 100Hz to 5kHz, with a specified maximum output voltage of 2 × 34V RMS.

Three audio inputs provide flexibility when connecting microphones and existing sound equipment. Two inputs are switchable between line and microphone operation, while a priority 100V input supports integration with a suitable public address system. A 12V / 2mA phantom supply is available for compatible microphones, and individual input gain controls allow source levels to be adjusted during setup.

Compression and automatic gain control help manage variations in audio level. Adjustable treble control from 0 to 9dB provides additional flexibility when setting the system’s audio response to suit the installation.

Front-panel indicators show power, input gain level and magnetic loop current, giving installers useful feedback during setup and routine checks. A 6.35 mm headphone output provides a local audio monitoring connection, helping with source checks and troubleshooting.

The integrated power supply accepts 90–265V AC at 50/60Hz, supporting fixed installation without a separate external power supply.

Loop design should account for room geometry, listening height and surrounding metal. Opus recommends a SmartLoop study to assess the intended listening area and plan the cable arrangement. Final commissioning should include field-strength measurements across the required coverage area to verify the completed installation’s performance.