therealdobro wrote:
So, the Noise Reduction setting can introduce artifacts if it's too aggressive, and that's why you set it relatively modestly for each pass? Or is it set that way because you do so many passes?
The lower the FFT setting, the more audible the artifacts will be, but the lower FFTs are more effective at lower frequencies. This means that you are forced really to use lower amounts of reduction with these, but you can generally increase the amount somewhat with higher values.
Lower FFT values analyse a larger 'chunk' of waveform, and it's the residual sound of these chunks that are the bubbly artifact you hear. With smaller chunks, the result sounds (rather perversely) much more like noise, or a spooky echo.