Thanks to Eric for his suggestions for making what may seem complex much easier. If it’s OK I’ll add a couple more thoughts one of which is that an EQ set at noon is not necessarily the “flat” setting for that particular amp. You may need to spend some time working with each tone control to find it or search for something someone else has posted online whose done this for you. Many amps have voicings that are far from neutral or “flat” when the EQ controls are set to noon.
The other is what’s covered in what I quoted above. What your rig will sound like at home in a small room isn’t what it will sound like in a larger more open room. What the crowd hears is also not what you hear standing a few feet in front of it. Many times the rig must be EQ’d for the room in a way you may not enjoy on stage but in that room it works perfectly. There were nights when I hated how I sounded on stage but if I walked out into the room to hear it I was shocked by how much better it sounded.
Good piece of advice in that last paragraph as well. Smaller tweaks on your amp should yield the right results if everything else has been done correctly first. Basses and Guitars have their own voices and ways to adjust them. Their controls should be effective enough to allow you to adjust those on the fly without any major changes in the amps settings. Effects are a whole other ball game so I won’t deal with that here.