tuning timbre spectrum scale

I am getting alot out of william sethares' book. A couple of days ago I was experimenting with my cello. I had placed a split shot sinker at various places along the legnth of the string. When played pizz the string rings like a metalophone. Sort of like Cage's prepared piano with the advantage of being able to alter the legnth of th string with my left hand. I got the idea about the split shot from Bart hopkin's book about building instruments. I cut my experiments short because I had just got new strings and I value their harmonicity.