When does an "old" bass become a "new" bass.

[Jeremy Darrow]

Over the long lifespan of antique instruments it's not unusual for integral parts to be replaced due to damage or for updates, like neck grafts. I'm curious if there is a consensus regarding when a bass that was made by one maker ceases to really be the original and becomes another bass. One that should not be referred to by the original makers name. For example, I think a replaced rib or two is perfectly reasonable, likewise for a neck graft. But once a bass has been re-topped, I have a hard time considering it the same bass it was before the repair.

What do the experts say? Thanks for reading.

Jeremy