Plena Power Amplifiers
Product range introduction
The Power Amplifier is part of the Plena product range. The Plena product range provides
public address solutions for places where people gather to work, worship, trade, or to relax. It
is a family of system elements that are combined to create public address systems tailored for
virtually any application. The Plena product range includes:
The various elements are designed to complement each other using matched acoustical,
electrical and mechanical specifications.
All Plena Power Amplifiers in this manual are designed for use in EN54‑16 and EN60849
Power amplifier range
The Plena Power Amplifier range consists of the following mono amplifiers:
In this manual all illustrations show either the LBB 1938/x0 power amplifier that is 3 units
high, the LBB 1930/20, LBB 1935/20 power amplifier that is 2 units high. All connections are
similar between the different power amplifiers. These power amplifiers have 70V and 100V
constant voltage outputs and a low impedance output for 4 or 8 Ohm loudspeakers.
Two inputs, "Priority" and "Program", give priority and controlled outputs. A 100V slave input
gives connection to existing loudspeaker lines. The line inputs are balanced and have a
loop‑through facility. The amplifiers have overload and short‑circuit protection. A temperature
controlled fan and overheat protection gives high reliability. Battery operation with automatic
switchover from the mains supply is available.
Bosch Security Systems B.V.
Music source unit
Digital message manager
Voice Alarm System
120W LBB 1930/20 (2 units high).
240W LBB 1935/20 (2 units high).
480W LBB 1938/x0 (3 units high).
Installation and Operation manual
System Overview | en
2014.01 | V1.1 | LBB193x/x0