Hi list, Sorry for the posting fowl-ups, and thanks for engaging me in this discussion. I have learned a lot (and have learned from the archived postings as well). I would like to suggest one last insight from my morning shower that I think has clarified much of this issue for me: Just as the effect of duplex scale damping on the sustain of the main segment is not patently obvious (i.e. requires quantification before we can all believe it), the inverse must also be true. That is, any effect of the damping of the main segment on the sustain of the duplex segment would be slight enough that it would not be obvious to all observers. This effect can be verified by plucking a duplex wire whose corresponding main segment is damped/muted. It rings for some time. What are the implications? Play a note that has both a damper and a duplex segment. Even play it harshly. Immediately damp the main lengths of the unisons. What we now hear (or should hear) is any residual vibration in the duplex segments. And thus the acoustic contribution of the duplex would no longer be a matter for speculation but would be isolated. (Note that this vibration would not be damped merely because the vibrations in the main lengths have been damped. We've already established that.) When we do this exercise, does the duplex still ring? It doesn't on my piano, but my duplex is slightly out of tune and of a possibly unconventional design. What do all of you find in your pianos? My piano has a rear duplex only. I can understand how a front duplex might be set to ringing, expecially on high notes. As the string rings, there would be a periodic flexion in the wire at its point of contact on the capo bar. The torque from this flexion would induce movement in the front duplex segment, i.e. with the piano wire acting as a lever and the capo bar acting as a fulcrum (implying no mechanical advantage here). In this way a transverse wave can cross a stationary contact. I have no experience with this sort of arrangement and have no opinions of my own as to the acoustic implications. Peace, Sarah
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