... ... From reading through here, it seems Rumble 500’s don’t love an active bass ... ...
Now, that's just a gross generalization, much like saying that all bassists love active basses!
I don't believe that has been established to be factual for Rumbles in particular, nor any amps I'm familiar with. Please don't let that prejudice you.Yes, I've read of some active basses that can cause clipping in various amps, especially some 18volt. But, not all active basses are the same, in that respect. I believe it's mainly a matter of getting to know your instrument and your amp and how they interact. You know the old Spider-Man adage of what comes with great power.
My R500c seems to absolutely love my active basses! But, I never dime my bass's bass boost nor volume. I always want to have some reserve (headroom?) available at my fingertips, just in case. And mine are just 9volt. Never had a problem, even when my country cover band slipped into a couple volume wars, in which I participated purely in self defense!

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Guess I shoulda done my research before spoutin' off! Good to know y'all got my back. Now . . .