Lab.gruppen PLM Series - Analog Input Examples and Speaker Configurations; Speaker Configurations; Digital Audio Connections

Application Guide
85
PLM Series Operation Manual rev 1.1.9
▸ Absolute Noise Floor: -71.5 dBu
▸ SPL is limited to -8.9 dB relative to clip in this minimum absolute noise level example
-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/dBu
Clip
Nominal
Noise
Figure 10-4: Analog: Low Noise with Limited Output (Low Input / Low SPL)
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
-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/dBu
Clip
Nominal
Noise
Figure 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