Lab.gruppen PLM 20K44 Operation Manual page 80

10. Application Guide
10.3.2. 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.
10.3.3. Gain Optimization Examples
This section provides examples on performance effects resulting from changes to the PLM+ gain structure
10.3.3.1. Digital Input Gain Structure Examples
• Input Clip: 0 dBFS
• Amp Gain: 35 dB
• SNR: 114.2 dB
• Absolute Noise Floor: -71.3 dBu
100,0
50,0
0,0
-50,0
-100,0
-150,0
Analog AES Input
-200,0
-250,0
Table 10.2: Digital Input: Low Noise with Good Headroom (High Input / High SPL)
Figure 10.3 illustrates how to achieve the lowest possible output noise, although this is not a recommended
• Input Clip: 0 dBFS
• Amp Gain: 22 dB
• SNR: 114.8 dB
• Absolute Noise Floor: -71.9 dBu
100,0
50,0
0,0
-50,0
-100,0
-150,0
Analog AES Input
-200,0
-250,0
Table 10.3: Digital Input Optimized for Minimum Noise - Not Recommended
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PLM+ SERIES Operation Manual rev 3.0.1
Input Mixer Module In Module Out Amp
Input Mixer Module In Module Out Amp
Attenuation Analog Ref Amp Gain ISVPL
Attenuation Analog Ref Amp Gain ISVPL
Clip
Nominal
Noise
Output
Clip
Nominal
Noise
Output