DO NOT NORMALIZE!
This is a very much misunderstood function.
What it does is finding the highest peak, and use that as a max.
If you did not mix with a brick wall limiter, chances are HUGE that nothing will happen if you normalize at 100%.
(Even one little unnoticable high peak, like from a raindrop or scissors will set the maximum level)
So it is highly unpredictable, and there will be a huge difference between your clips.
If you mix to -12 with peaks to -9, you can add 9 dB gain and your peaks are still safe. But there WILL be some distortion then. (small peaks that you cannot see.)
Adding 6 dB probably gets you where you want to be without any effort.
But again, adding a brickwall limiter first is the best way to go. After that it does not make a difference if you use gain or normalize.
Bouke
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