What’s the best way to add acidity, and how will that change the TA?

The best way to add acidity is: slowly and carefully! As discussed in this BLOG post, add half the amount you think you need, then re-check pH and TA to see where you are.

When you add acidity with tartaric acid (as we recommend) then the TA just goes up by the amount you added (in g/L).  As we’ve discussed in the above mentioned blog post, the decrease in pH that this effects depends on the TA (buffering) ability of the wine.