Lab.gruppen PLM 20K44 - Manual (Page 79)

10. Application Guide
PLM+ SERIES Operation Manual rev 1.0.0
79
Figure 10.5 illustrates how to minimize absolute noise while achieving full power. In this illustration it can be seen
that there is no available headroom.
• Input Clip: 12 dBu
• Amp Gain: 30.9 dB
• SNR: 111.3 dB
• Absolute Noise Floor: -68.4 dBu
Table 10.5: Analog: Low Noise with Full Output Power (Low Input / High SPL)
Figure 10.6 illustrates how moderate noise with extreme SPL can be achieved. SPL is extremely high in this
example as maximum headroom is available at the input and within the processing stage. This makes it possible to
increase the average SPL by utilizing internal compression capabilities.
• Input Clip: 0 dBFS
• Amp Gain: 35 dB
• SNR: 114.2 dB
• Absolute Noise Floor: -71.3 dBu
-140.0
-120.0
-100.0
-80.0
-60.0
-40.0
-20.0
0.0
20.0
40.0
60.0
Analog AES Input Input Mixer Module In Module Out Amp Attenuation Analog Ref Amp Gain ISVPL Output
dB
/d
Bu
Clip
Nominal
Noise
Table 10.6: Analog Input: Moderate Noise with Very High Output (Very High SPL)
-140,0
-120,0
-100,0
-80,0
-60,0
-40,0
-20,0
0,0
20,0
40,0
60,0
80,0
Analog AES Input Input Mixer Module In Module Out Amp Attenuation Analog Ref Amp Gain ISVPL Output
dB
/d
B
u Clip
Nominal
Noise