Bosch Plena System Pre-Amplifier LBB1925/10

Product Description

• Six-zone system pre-amplifier,with single or dual channel operation

• Two input channels for call stations

• Universal input for microphone/line,with speech optimized tone control

• Three inputs for BGM selection and music optimized tone control

• Front panel zone selection for BGM and call station zone selection for calls

• The Plena system pre-amplifier is a versatile,high-performance unit with call and mono BGM (background music)

• It fulfills a wide variety of public address requirements at a surprisingly low cost

• It can provide dual channel operation for simultaneous calls and BGM for up to six different zones,using two Plena amplifiers

• Functions

• The call channel provides two inputs for the Plena call stations,LBB 1941/00 (all-call) or LBB 1946/00 (six-zone),with loop-through capability,and universal,balanced input

• One is a 3-pin XLR connector for microphone or line level (selectable),and the other is a 5-pin DIN-connector with all-call priority contact,which may also be used to start one of the available chime attention signals

• The microphone input has a selectable speech filter for improved intelligibility,a volume control,and bass and treble tone controls with shelving characteristics optimized for speech

• The call channel is available on the balanced XLR master output

• The BGM channel provides three inputs on stereo cinch-connectors, converted to mono,with front panel selection,volume control and bass and treble tone controls with shelving characteristics optimized for music

• The BGM channel has a direct output on balanced XLR for dual channel operation

• It can also feed the master output,with the lowest priority,for single channel operation

• Zone selector switches on the front panel control the BGM routing

• An overload protected 24 VDC output provides power for driving external relays,often making an external power supply unnecessary

• An emergency/telephone input with signal level detector (VOX) and volume preset has the highest priority to all zones

• Two trigger inputs (contact closure) activate alarm or time signals to pre-selected zones

• Many different chime tones are available

• A PC audio input with RS-232 control provides software controlled zone configuration,or automatic messaging in combination with the LBB 1965/00 Plena Message Manager

• There are six levels of priority available for BGM,microphone,call stations, trigger inputs and emergency input

• A set of relays directs the amplifier output(s) to different loudspeaker groups (zone switching)

• Each zone has a tri-state control on the front panel that can turn it off, switch it to the call channel,or to the BGM channel

• The all-call microphone input and emergency activation override the call station selection on the call channel

• Each zone has separate priority overrides with preset volume levels

• This assures an appropriate message volume,independent of any local volume settings,such as for BGM

• Both three-wire and four-wire override schemes are supported

• An override also activates a voltage-free contact (call-active) available for external control and monitoring

• The master output channel,or one of the input channels,can be monitored through the headphone connector and/or the LED VU-meter

• Controls And Indicators

• Front

• LED power meter

• Power on LED

• Call active LED

• Three knobs for mic/line volume, treble, and bass levels

• Three knobs for BGM volume, treble, and bass levels

• BGM source selection knob

• Six zone-selections keys

• Six zone status LEDs

• On/off switch

• Back

• EMG input volume control

• Mains voltage switch
  Interconnections

• Front

• Headphone jack

• Back

• One (DIN or XLR) Mic/line input

• Two (DIN/DIN) call station inputs

• PC audio (cinch) input

• Priority input

• Master (XLR) output

• BGM (XLR) output

• Emergency signal input

• Two trigger inputs

• RS-232 (DE-9)

• Three (cinch) CD, tape, aux inputs

• Six 100 V speaker outputs

• 24 VDC output

• 24 VDC input

• Three control inputs

• Ground screw

• IEC mains socket

Product Specification

Other Details