The Essentials of Power

Flexibility: PLM 10000Q – 4 × 2700 W, PLM 14000 – 2 × 7000 W, PLM 20000Q – 4 × 5000 W

The PLM™ Series is designed to meet the demanding requirements of mid- to large-sized sound reinforcement systems – including modern line array designs – with ample undistorted power and generous headroom. With the PLMs, you can run boxes in parallel down to 2 ohms with abundant headroom reserves.

Replacing conventional amplifiers with higher-power, flexible PLM Series units will reduce your rack space and footprint considerably, and will also reduce or eliminate the need for external processors. A few small racks with a total weight of less than 100 kg (221 lbs) can supply ample power, processing and control for one side of an arena-sized system. And, with PLM Series’ ease of reconfiguration, those same racks can be reset for use with monitor systems with point-and-click ease.

Indeed, any system of any size comprising many different cabinets can be powered in a snap with PLM Series. That’s just one inherent advantage of the Powered Loudspeaker Management™ concept. Finally, when you factor in the size and weight reductions for a total system, the savings in labor and truck space translate into lower costs in touring applications. In permanent installations, the venue owner benefits from the additional space available for other uses.

Protection

Lab.gruppen’s PLM Series incorporates comprehensive warning and protection features to safeguard the PLM itself and all connected loudspeaker drivers. Front-panel indicators (replicated in the Lake® Controller software) give clear warnings when any potential problems are detected.

Protection measures are enabled only when critical thresholds are passed. Measurements are re-checked every few seconds, and normal operation resumes automatically when nominal conditions are restored. The complete protection and warning suite includes DC at output, short circuit, excessive output current, sustained Very High Frequency (VHF), and open load.

The PLM Series also includes a Power Average Limiter (PAL) to guard against inadvertent tripping of the mains fuse or external circuit breakers, either during a performance or at start-up. While in operation, PAL constantly monitors the current-drawing relationship between the power supply and the mains inlet to ensure that current demands stay safely under nominal breaker thresholds.

If conditions are detected where the power amplifier could draw more than the mains inlet can supply, PAL limits current draw to prevent power interruption. Additionally, a soft-start circuit limits initial current draw when a PLM is turned on.

New for PLM 20000Q is the software-controlled Breaker Emulation Limiter (BEL™) to avoid tripping mains breakers even with prolonged peak demands and Under-Voltage Limiting (UVL™) that enables continued operation with mains voltage sags as low as 65 V.

Intercooler® for efficient, uniform cooling

The compact and ultra-efficient Intercooler uses thousands of tiny cooper cooling fins to increase exposure of the heat sink to the cooling air flow. Twin variable-speed fans respond to temperature sensors, forcing air over the Intercooler fins in a front-to-rear flow.

All output devices are mounted transverse to the airflow, so the cooling effect is uniform. In PLM Series power output sections, there are no “end of tunnel” output transistors subject to greater warming and, consequently, possible premature failure.