You don't have to raise pitch to make an instrument sound brighter, at least on a stringed instrument. Experiment with strings till you find a sound you like.

I have gut strings now on one of my fiddles, and the sound is ANYTHING but "bright." But since I do period music, they're on there for a reason. I also have discovered why something better was invented. :-)

One thing I wonder about, though, Don, is that if tuning wasn't really standardized, how do we know that Mozart's Ab wasn't Beethoven's F#?

Mister and I have been in the situation once or twice, where we simply had to tune to each other and not worry about whether or not we were in "concert" pitch. It works out pretty well that way.