I think the ambient noise reduction is enabled by default in macOS Catalina, resulting in very poor audio quality using Rode plug-play microphone!

Is there any terminal command to disable ambient noise reduction in macOS Catalina?

As you can see the option made invisible in audio input settings since Catalina. Very unexpected form Apple!

Solution

Re-installed macOS Mojave (I decided not to update to macOS Catalina at any cost)! Here is the screenshot from macOS Mojave with ambient noise reduction option.

My understanding is that the "Ambient Noise Reduction" feature only works with the internal microphone. Thus when you plug-in a Røde USB microphone, ambient noise reduction is not applied to that input. Therefore I suggest looking at other possible causes of bad audio quality or latency.

The lack of the checkbox for the internal microphone on Catalina is, as I understand it, a bug. Hopefully Apple will restore it in a point update.

Unfortunately there doesn't seem to be a Terminal command that enables/disables ambient noise reduction. You might however want to check if the plists in the /Library/Preferences/Audio/ folder contains a setting related to ambient noise reduction on your system.

However Apple's documentation seem to indicate that you can disable ambient noise reduction by setting up a 4-channel built-in microphone format with the Audio MIDI Setup program.