..and I have mine set relatively close. So, you have to figure this out by yourself :)
My advice: set it really close at first, then start lowering it and listening. Go through to a low height, and then take it really close to strings again. Now you have a rough image on what it sounds at different heights, and perhaps know roughly where it would be best. Just approach that height and finetune. Your ears are the judge; if it sounds good, it is good.
-Zaned