mmm B-basis and A-basis (that’s how we define it in my work-world) calculations on normal tolerance distributions. We have a lot of sciencey/engineer types in here huh?
Tolerance stack-up can definitely lead to changes, I’d say. Quality engineering is a bit dry, but these types of things matter quite a bit – understanding what your end goal is and all the process capabilities of your design and process are and then dealing with how the tolerances of each and every component stack up and affect the end item.
On balanced vs unbalanced. Some times I hear a big difference and sometimes I do not. I go balanced as often as I can, because I can. At the very least, you get much more ample head room and power. At best, you get less interference/cross-talk and more magic audiophile powers. Nothing really wrong with that.
Go Science! Go Subjectivity!