One benefit of variable gain setting is that you can match up the average loudness of your phono listening with the average loudness of your CD listening. When your source selector clicks back and forth between phono, and CD you won't suddenly be "blasted" by your baseline or default volume control setting.
Of course, once you develop a taste for the vinyl good stuff, there may be a falling off in frequency of CD listening :>)
Of course, once you develop a taste for the vinyl good stuff, there may be a falling off in frequency of CD listening :>)

