AKG CK 61-ULS Bedienungsanleitung Seite 19

The following values for Rv (or 2 x Rv) are stan -
dardised:
U = Rv
48 V ± 4 V 3300 Ohm
The resistors 2 x Rv have to be of at least 0.5 %
tolerance type to satisfy the symmetry requirements.
2 x Rv
6800 Ohm
In case where single ended (grounded) amplifier
inputs, or where no input transformers are available,
either capacitors or optional transformers have to be
wired into the audio lines to prevent any current
leakage into the input circuitry.
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