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PLM Series Operation Manual rev 1.1.3
12. Application Guide
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.
Figures 12a through 12.2c demonstrate how altering the gain structure within the PLM affects performance.
When using AES (or Dante) inputs:
Figure 12.2a and 12.2b illustrate the recommended configuration of the PLM when using a digital input
source.
Parameter list:
Input clip: 0 dBFS
Amp gain: 35 dB
SNR: 14.2 dB
Absolute Noise Floor = -71.3 dBu
Figure 12.2b illustrates how to achieve the lowest possible output noise; however, this is
not
a recom-
mended setup
Parameter list:
Input clip: 0 dBFS
Amp gain: 22 dB
SNR: 114.8 dB
Absolute Noise Floor = -71.9 dBu
Gain Structure: "High SPL - Low noise - Good headroom"
-250,0
-200,0
-150,0
-100,0
-50,0
0,0
50,0
100,0
Analog
AES Input
Input Mixer
Module In
Module Out
Amp
Attenuation
Analog Ref
Amp Gain
ISVPL
Output
dB
/d
B
u
Clip
Nominal
Noise
Figure 12.2b: Gain structure: Digital input source
Gain Structure: "High SPL - Low noise - Good headroom"
-250,0
-200,0
-150,0
-100,0
-50,0
0,0
50,0
100,0
Analog
AES Input
Input Mixer
Module In
Module Out
Amp
Attenuation
Analog Ref
Amp Gain
ISVPL
Output
dB
/d
B
u
Clip
Nominal
Noise
Figure 12.2a: Gain structure: Digital input source
