Comparing sustain on different basses seems to be a somewhat subjective exercise. The method I have heard espoused is to pluck a string and time how long you can hear it. So, you are never going to pluck the string the exact same way any two times, and you may not hear the end of the audible portion of the vibration consistently. This may be close enough for most purposes, but I have been wondering about using a more consistent, repeatable process that would aid in a more objective comparison between instruments. Sustain is just a form of decay, not too dissimilar to radioactive decay, I think. Radioactive decay is measured in half-life. Could this also be applied to the decay of sustain? Pluck a string, and, using an oscilloscope, record when the amplitude of the tone generated is half of what was initially plucked. This time would be the half-life of the instrument's sustain. Do that for each string and you might have a specification that could be objectively compared between instruments. Now, I'm not an engineer, so I could very well be missing something, but I would like to hear what others think about this. And no, I have not been drinking more whiskey than is considered helpful... EDIT: I really only care about having enough sustain to carry through maybe a couple of bars at the most. My reason for bringing up this question was centered around the fact that discussions about sustain didn't have a way to objectively compare basses. Using the methodology that is applied to radioactive decay seemed like it might be a possibility. It is more idle curiosity than anything else.