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PLM Series Quick Start and Field Reference Guide rev 1.0.6
6. Quick Start Tutorial
settings in the output stage of the module were configured with this gain setting and will not be automati-
cally compensated if changes are made. This configuration scheme, though unusual, allows for backwards
compatibility with other Dolby products. (Set in Lab.gruppen Info, Control tab.)
6.6 Gain / Level Optimization
Optimum setting of the PLM gain structure requires particular attention to two matters:
Make sure it can get loud enough.
To do this, the user should ensure that there is sufficient headroom in the signal path to avoid clipping
before you reach the limiters. At the same time, it must be possible to achieve enough gain through the
PLM to engage the limiters and realize a high average SPL as a consequence. 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
input gain on the module.
Minimize the noise.
As a first step, use a digital input signal (AES or Dante) when possible. If using analog inputs, ensure that
headroom is not introduced on the input side that is unused or unreasonably high. If full power is not
required, or at least not a high average power, you may also lower the gain on the input of the module.
Figure 6.5: PLM Signal Flow Diagram (Part 1)
Input
Router
1
(Mute)
Input
Router
2
(Mute)
Input
Mixer A
Input
Mixer B
EQ
Delay
EQ
Delay
Crossovers
Output Routing
AMP
Attenuator
Mute
Phase Rev
Attenuator
Mute
Phase Rev
Attenuator
Mute
Phase Rev
LoadSmart
SpeakerSafe
LoadSmart
SpeakerSafe
LoadSmart
SpeakerSafe
LoadSmart
SpeakerSafe
Amp Gain
Amp Gain
Amp Gain
Amp Gain
Attenuator
Mute
Phase Rev
Module:
Gain
Phase Rev
Mute
Analog 1/2
AES 1
AES 2
Dante X
Dante Y
Analog 1/2
AES 1
AES 2
Dante X
Dante Y
AMP
AMP
AMP
ISVPL
ISVPL
ISVPL
ISVPL
Module:
Gain
Phase Rev
Mute
Output EQ
LimiterMax
RMS / Peak
Module Output:
Gain/Level
Phase Rev
Mute
Output EQ
LimiterMax
RMS / Peak
Module Output:
Gain/Level
Phase Rev
Mute
Output EQ
LimiterMax
RMS / Peak
Module Output:
Gain/Level
Phase Rev
Mute
Output EQ
LimiterMax
RMS / Peak
Module Output:
Gain/Level
Phase Rev
Mute
Output EQ
LimiterMax
RMS / Peak
Module Output:
Gain/Level
Phase Rev
Mute
Output EQ
LimiterMax
RMS / Peak
Module Output:
Gain/Level
Phase Rev
Mute
4
1
2
3
1
2
3
5
6