Hello Rich and welcome to the Cow Audio Forum.
“Background Noise” is bad, but to which background was he referring? You are correct that gain is gain.
Each gain stage, trim pot and mic fader, has a center point of operation at which you get the best performance. When you exceed that level, the normal consequence is increased noise.
So having one of the two controls turned WAY UP may bring up system noise, which can loosely be construed as background noise – normally hiss.
” I had always considered variable gain as sort of a rough level control and the pot or fader as a fine level control.”
You are entirely correct!
“What I inferred from this is that the gain will also make a mic more sensitive to lower noises, which seems a bit illogical, but may be the case.”
You are also correct. This is illogical and does not occur on this planet, e.g. if you’re getting a feed from the house that’s noisy, turning down the pot to reduce the house noise and expecting it to remain lower while you raise the fader is silly. The damage has been done and you can not unbake that cake.
The general rule of thumb is to do the heavy lifting with the pot but stopping before it llghts the peak or limiter lights so that the fader (at least for the 552, 442, 302) normally rests at 12 o’clock; allowing you to easily turn the fader up and down (within its preferred range) as needed.
Regards,
Ty Ford

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