Whichever direction or product you choose I'd recommend one that allows you to use a reference song -- not just to listen to but to let the app create that sound in as much as possible. We use Ozone. Feed it the reference tune and it will do its thing in about 10s and create a module chain that you can tweak away to your satisfaction.

From our current productions to songs we recorded live on a tiny cassette recorder many years ago we continue to be impressed with the results. I know you expressed no interest in a mastering app per se but even if you don't tweak the results they still way improve the mix and all with a few clicks. No doubt there are many other options, And FWIW this mercifully doesn't have anything to do with AI.

Bud

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