If you CS that wine, the pH will decrease, see the attached clip below from PSU. When the pH is below 3.6, CS DECREASES the pH (increase acidity). If your pH was above 3.6, CS would increase the pH (decrease acidity). If you want to increase the pH, look to one of the products that will increase your pH WITHOUT the need for CS to precipitate out the acid.
Sorry for all of the chemistry talk below. The referenced chart didn't come through in the cut/paste, but the information about the pH reaction to CS in the last paragraph is the important part........
"Theory of Cold Stabilization
Cold stability is a method of separating unstable natural ionic salts (potassium: K+, calcium: Ca2+, bitartrate: HT-) from wine. After fermentation, but prior to bottling, cold stability is conducted to prevent the tartaric salt, bitartrate (HT-), from precipitating out of the wine when stored and/or chilled post-bottling.
Precipitation occurs due to the instability of tartaric acid in its bitartrate salt form, which is known as potassium hydrogen tartrate (KHT) as a supersaturated solution. KHT is commonly referred to as potassium bitartrate or cream of tartar, and accounts for much of wine’s sourness or tartness (Butzke 2010). Instability occurs when the concentrations of potassium (K+) and bitartrate (HT-) bind to form the KHT product that exceeds solubility in the wine (Iland et al. 2004), thus precipitating out of the wine.
The pH of wine should be checked prior to cold stabilization as pH affects the efficacy of stabilization techniques. A higher pH wine (>3.6) will precipitate out more KHT in comparison to a lower pH wine (<3.6) (Church 2004). This is due to the percentage of the HT- present in the wine at a particular pH. The amount of tartaric acid in HT- form, as a function of pH, is illustrated by the acid stability curve seen in Figure 1.
boultontartaric acid chart
Figure 1 was provided courtesy of Dr. Roger Boulton in 2012, University of California, Davis.
As seen in Figure 1, the maximum concentration of bitartrate (HT-) exists at pH 3.6. At such pH, there is much available substrate to bind with K+ to form the KHT product. As a result of KHT precipitation, the titratable acidity will decrease. However, changes in pH are a result of the initial pH prior to cold stabilization. A direct relationship between pH value and percentage of HT- occurs. If the initial pH of the wine, prior to cold stabilization is below pH 3.6, then the pH will decrease as KHT precipitates out of solution. If the initial pH is above pH 3.6, then the pH will increase as KHT precipitates out of solution (Iland 2004)."
EDIT: If you'd like to read the whole article, you can here:
http://extension.psu.edu/food/enology/analytical-services/cold-stabilization-options-for-wineries