The L-Acoustics MTD115 LLCa is a dedicated analog line-level controller designed to optimize and protect the legacy MTD115 series of coaxial loudspeakers. It provides essential signal processing, including frequency crossover, equalization, and “sense return” protection to prevent driver damage from overheating or excessive excursion.
Controller Functions & Modes
The LLCa (and related LLC115b models) provides three selectable operating modes to tailor the speaker’s performance to its application:
- FRONT Mode: Optimized for medium-power Front-of-House (FOH) use, providing a 3 dB low-frequency contour under free-field conditions.
- MONITOR Mode: Tailored for floor wedge use with a 45 Hz high-pass filter to manage stage resonance.
- X-OVER Mode: Activates a 100 Hz high-pass filter, specifically for use when the MTD115 is paired with subwoofers like the SB115 or SB218.
- Sense Return Protection: A critical feature where the amplifier output is fed back into the controller via Speakon connectors. This allows the controller to monitor actual voltage and apply RMS and peak limiting in real-time.
