Midas DL431, Operator'S Manual

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DL431 Mic Splitter
Operator Manual
Chapter 8: Application Notes
Using the 30Hz filter
The DL431 Mic Splitter’s 30Hz filter is an analogue high pass filter (HPF). It is a very
low frequency signal filter with a 30Hz corner frequency and 12dB per octave
Butterworth roll off. This filter can be switched into circuit following the mic amp to
make better use of the A/D conversion headroom by removing the very low frequency
audio content.
High pass filters are used to remove unwanted subsonic frequencies, which are
traditionally about 30Hz. A typical use for this filter is to reduce rumble.