Operation Manual

23
DL431 Mic Splitter
Operator Manual
Appendix A: 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 analogue-to-digital (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.