Quick question, lately I have been getting tightness in the muscles between my shoulder blades. Usually my DB stands so that the nut is right at my eyebrows. I noticed today when I adjusted it so the nut was about 2 inches higher that the tightness wasn't there. I think it is from leaning too much so I can bow close the bridge. Is there a hard and fast rule to the height of the bass? Most things I have read say nut at eyebrow. Seems a little easier to play with it up higher.