When I got my 9 string I immediately bought the ernie ball 9 string set just because I wanted the .105 for the c# with the intention of dropping it to a. But holy shit did that buzz like crazy, only when not fretted. I put paper in the nut slot for that string and it fixed it but it gave a weird buzz so I just got rid of it and went back to a .90 . I was just curious If anyone has any tips for me or anyone else who is curious as well. If it matters its 30 inch scale.