Schoeps LC 120 U Active Low-Cut Filter 120Hz, XLR
These electronic filters can be inserted anywhere in the microphone cable path. With a rolloff of 18 dB/octave, the LC 60 U suppresses low-frequency acoustic interference (e.g. wind noise, or solid-borne infrasonic noise such as handling noise during boom operation) without detracting from the sound quality of voice recordings. Under extreme conditions the LC 120 U can be used, though it may have an audible effect on the sound of a voice. Both filters can help prevent overloading the input circuit to which a micro phone is connected – a problem which occurs more often than many people realize.
The LC 60 U and the LC 120 differ merely in their cut-off frequencies, these being 60Hz and 120Hz respectively.
- active low-cut filters for phantom-powered microphones, in particular CCM compact condenser microphones and CMC microphones of the Colette modular system
- for standard phantom power, 12 V or 48 V
The specifications of the SCHOEPS microphones (sensitivity, noise, source impedance) remain nearly unchanged with the LC.
These low-cut filters are suitable not only for SCHOEPS microphones but also for phantom-powered microphones of other manufacturers, provided that they have a current consumption of at least 2 mA. Otherwise the maximum sound pressure level would be reduced.
The use of two LC in series is possible, particularly with SCHOEPS microphones, but is not recommended. The cutoff frequency would be raised, and the maximum output level with 12-Volt operation would be lowered. In no case should three LC be cascaded, especially if the microphones have less than 4 mA current consumption.
|LC 60 U, LC 120 U
||In-line low-cut, Butterworth, 18 dB/octave
||LC 60 U: 60 Hz, LC 120 U: 120 Hz
|Maximum output voltage
Frequency response of the LC 60