Another problem with microphones is that if the talker is too close then every plosive (a consonant with a puff of air like a “p”) causes a mini explosion. This also occurs with fixed microphones if the speaker bangs their hand on the podium. The solution to this problem is a “De-Popper” which is another form of dynamics processor. Instead of focusing on high frequencies like the De-Esser the focus will be on low frequencies below 150 Hz. The derivative of low frequency energy (i.e., changes in energy over time) engages the limiter only for positive slopes. The block diagram is shown below:
The RMS module computes the energy over a 40 msec running window and the derivative module looks for changes in energy. Constant low frequency energy doesn’t trigger the limiter at all.