AKG Discreet Acoustics Mode D'emploi page 27

If your equipment inputs are grounded or transformer-
less, wire either capacitors or extra transformers into the
audio lines as shown in fig. 8 in order to prevent any cur-
rent leakage into the input stage.
Table 2: Standard values for Rv and 2 x Rv
VDC
12 V ±2 V
24 V ±4 V
48 V ±4 V
* In order to satisfy the DIN 45596 symmetry requirement,
make sure the actual values of the two resistors 2 x Rv
do not differ by more than 0.5%!
All installation modules except for the LM 3 and LM 3 L
feature an LED ring that lights to indicate the sound
system is ready to operate.
The LED rings on these Installation Modules operate off
phantom power.
If you connected the microphone correctly, the LED ring
starts glowing at moderate intensity as soon as you switch
4 Installation and Connections
Rv
330 Ω
680 Ω
3,300 Ω
4.6.2. Unbalanced
Inputs
Fig. 8: Unbalanced
input stage
2 x Rv*
680 Ω
1,200 Ω
6,800 Ω
4.7. LED Ring
4.7.1. GN 15,
GN 15 E, GN 30,
GN 30 E, GN 50,
GN 50 E, HM 1000
Installation
Modules
27