What does it mean?
Noise reduction may use spectral processing, adaptive filters, or machine learning. Rigs provides Input Noise Reduction using a learned profile; it is not a separate pedal. Aggressive reduction can affect transients, sustain, and latency.
ExampleMute the strings during the three-second Learn noise step, then use only as much Reduction as needed and check Listen removed noise.
How the meaning changes between controls
Input
Noise Reduction runs before Trim, EQ, and pedals, using the profile for the selected device and channel.