In designing the new E Series, Lab.gruppen engineers drew upon the cutting-edge amplifier design philosophies developed for the flagship PLM™ 20000Q Powered Loudspeaker Management system, evolving these to create new circuit topologies and control features to meet the demands of 21st century AV installations. The result is a new amplifier platform called IDEEA: IntelliDrive Energy Efficient Amplifier. The principal design challenge was maintaining Lab.gruppen’s impeccable sonic performance and robust power output while meeting – or exceeding – the rigorous efficiency requirements of Energy Star 2.1 certification. The challenge was met on two fronts: reducing current draw during operating cycles with vigorous program material and high output levels, and reducing power consumption during non-operational cycles.
New power supply and output stage
For peak operating efficiency, the E Series incorporates a new high-headroom universal power supply accepting any mains voltage from 70 to 265 V at 50 or 60 Hz. A higher storage capacity in the power supply prevents excessive draw on the mains inlet during repeated peak bursts, maintaining extra headroom on the supply rails for sustained maximum output with minimal distortion. The Class D output stage is highly efficient (above 90%), while the inherently bridged topology allows up to twice the rated power output on one channel when the other channel is unused or driving a low power application. RSL™: Mix, match and balance loads The new Rail Sensing Limiter (RSL) is the latest refinement of Lab.gruppen’s proprietary approach to optimizing amplifier output characteristics to match the connected load. Each channel has a two-position switch that sets the output for driving either low impedance or high impedance (70 V) loudspeaker systems, with a +4 dBu sensitivity regardless of load type. RSL works in
conjunction with the high headroom power supply and inherently bridged output stage to allow asymmetric loading. Power resources in the amplifier can be utilized to maximum advantage, with one channel producing far beyond its rated output when the other channel has lesser power requirements.