Lab.gruppen C Series 5:4X - Manual (Page 22)

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C Series C 20:8X, C 10:8X, C 10:4X and C 5:4X Operation Manual rev. 1.1.4
Operation and Performance
The adjustable VPL (Voltage Peak Limiter) sets the maximum channel output voltage and therefore also the
maximum channel output power. Four different voltage stages are available using the DIP-switches on the rear
panel.
The sophisticated output section monitors faults and generates appropriate warnings, which are displayed on
the amplifier and transmitted through the NomadLink network. These alerts allow the operator to adjust system
settings and thereby avoid problems. In the rare event that conditions are extraordinarily severe, the amplifier
will shut down until the fault or problem setting has been rectified or adjusted. These sensing circuits are also
feed back voltage and current level information, via a side chain, to the limiters. Sensing circuits also transmit
local amplifier module temperature and power supply temperature to the appropriate protection mechanisms.
Please refer to the Protection, Faults and Warnings section for further details.
5.3.2 Headroom, sensitivity and VPL / Gain settings
The input amplifier and limiter system is designed to accommodate extremes of performance. Typically,
exceeding maximum input by much as +10 dB will only result in a 1% increase in distortion.
If you use the level potentiometer in the signal chain
to reduce the level by an amount greater than the
headroom relative to input sensitivity, AND you drive
the amplifier to clip level, you are in danger of
clipping the input stage before the current or voltage peak
limiters are activated
5.4 Audio Input and Output connections, setup and features
5.4.1 Balanced / Unbalanced Input connection
Figure 6.4.1: Phoenix-type input connector field
Electronically balanced, Phoenix-type inputs are provided on all channels. Follow the +,– and Ground labels
when connecting the input signal.
When bridging two channels, you must add 6 dB to
the input sensitivity to achieve maximum output
voltage due to the automatic -6 dB gain compensa-
tion inserted by the amplifier.