![](/images/new-backgrounds/1132108/13210821x1.webp)
Plena Mixer Amplifier Installation and Operating Manual Internal settings
en 11
2.3 Setting the chime volume
Adjusting the potentiometer VR401 changes the volume of the chime attention signal, preceding a priority call. Be careful not to adjust VR701; this is a power amplifier factory adjustment.
2.4 Setting the output voltage for LBB1903, LBB1906 and LBB1912
Direct outputs for 70 V, 100 V and low impedance (8 Ohm) loudspeakers are provided. Jumper JP802 sets the Call Only and Mix Only outputs to 70 V or 100 V output. These outputs are controlled by a priority relay. The Call Only output only provides priority announcements, while the Mix Only output just provides the mixed signals and switches off at priority calls.
2.5 Setting the output voltage for LBB1914
Jumper JP901 sets the Call/Mix, Zone 1, Zone 2, Call Only and Mix Only outputs to 70 V or 100 V output. Setting JP902 can also set the direct Call/Mix output to 8 Ohm for low impedance loudspeakers. The Call Only and Mix Only outputs are controlled by a priority relay. The Call Only output only provides priority announcements, while the Mix Only output just provides the mixed signals and switches off at priority calls. The zone selection buttons control the outputs of Zone 1 and 2, but priority announcements are always routed to these zones.