Lab.gruppen PLM 20000Q - Manual (Page 94)

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Application Guide
PLM Series Operation Manual rev 1.2.3
10.3.5 Attenuator
An attenuator gain adjustment is provided for each power output channel in the PLM. This control replaces
the traditional volume control found on conventional amplifiers and should typically be left at 0 dB during
use.
To adjust, navigate to I/O CONFIG > EVENTS & CONTROL > STATUS in the Lake Controller. Please refer to
the Lake Controller Operation Manual for further details.
10.3.6 Amp Gain
The Amp Gain corresponds to the gain adjustment in a conventional separate loudspeaker processor and
amplifier system. When using a pre-defined Module loudspeaker preset file, the Amp Gain settings will
normally remain as defined in the file. The limiter and output gain settings of the Module were configured
with this gain setting and will not be automatically compensated if changes are made. This configuration
scheme, though unusual, allows for compatibility with legacy Dolby / Lake products.
When creating a loudspeaker preset Module file, adjust by navigating to I/O CONFIG >
EVENTS & CONTROL > CONTROL in the Lake Controller. Please refer to the Lake Controller Operation
Manual for further details.
10.4 Gain / Level Optimization
10.4.1 Maximize Volume Capability
To maximize the volume capability of the device, ensure there is sufficient headroom in the signal path to
avoid clipping before the limiters engage. It must be possible to achieve enough gain through the device to
engage the limiters and realize a high average SPL. As an optimal setting, allow for a headroom of 10 dB or
more for all channels; the simplest way to accomplish this is to increase the Module input gain.
10.4.2 Minimize Noise
To help provide the best volume to noise ratio, use an AES or Dante digital input signal wherever possible. If
using analog inputs, ensure that unused or unnecessarily high headroom is not introduced at the input to the
device. If full or high average power is not required, the Module input gain may be reduced.
10.4.3 Gain Optimization Examples
This section provides examples on performance effects resulting from changes to the PLM gain structure.
10.4.3.1 Digital Input Gain Structure Examples
Figure 10-2 illustrates the recommended configuration of the PLM when using an AES or Dante digital input.