Looking for black coloration but with the taste of an amber. I’ve tried a couple of times various things and this next time I intend to try using the Midnight Wheat (1/2 lb) just in the sparge. After the first runnings I add 3 separate additions of sparge water, stir, and wait about 10 mins before draining and repeating. If I doctor my water for the amber and allow the MW to sit as I do will it effect the pH (I shoot for around 5.44)?
I presume you mean you are targeting wort pH 5.44 into the kettle? I would expect it to be pulled down some, yes. How much I don't know.
You can try some other tricks to get color with minimal flavor. The longtime British practice was to finely grind black malt and add it directly to the boil near the end. Other related methods are to do a separate "mash" (hot steep) or cold steep of the color malt and add this liquid to the boil. I've tried the steep methods and flavor is minimal, but it takes a lot of black malt (or MW, which I really do like for this purpose) to get the expected color.
As mentioned in the above post, Sinamar is a great colorant. It's in the class of products called Farbebier (color beer) in Germany. It is a dark beer -- fully brewed, with a very hefty portion of dehusked Carafa, fermented, and then vacuum concentrated into a dense syrup. A little goes a long way in terms of color, and while it does add a subtle roast flavor, it is indeed very subtle (my latest Dunkel using only extra Sinamar in place of 1% dehusked Carafa 2 is very obviously missing a roast note I now miss.)
Finally, if you are willing to pay ridiculous shipping, British homebrew retailers sell homebrew scale bottles of Brewers Caramel (aka Class III Ammonia Caramel,) the British standard colorant. Unfortunately, in the US you have to buy it by the drum.*
At any rate, any of these methods involve adding the colorant late in the boil, when you want to lower pH anyway, so any such effect is not a problem.
*Due to its charge, ordinary burnt sugar caramel coloring is not beer stable; it will bind with the body and foam positive proteins in beer, and the complex will precipitate out.