The feedback section is essentially a slapback effect. When using megaphones, the output of the loudspeaker can be captured again by the input microphone, introducing a delay/reflection and the usual feedback tones (those can be triggered with high gain sources and feedback amount higher than 50%).
Noise
The megaphone noises can be enabled by the Trigger button. There are two types of noise: Button and Burst. You can balance the mix between the two noises with the Source parameter. The button noise is the noise made by clicking on the megaphone button to enable its microphone. The burst is the typical background noise of the loudspeaker. If the envelope is enabled, the Burst noise will follow the transients of the input signal.
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