Del: To continue an ongoing discussion, I have some questions re your article in the PTJ August 1995. I am restringing a ca 1978 SS Model B. One of the problems is that it is very noisy in the capo section. I believe this problem can be traced in part to the capo bar being poorly shaped, which I will remedy. However, I am also concerned about the shape/position of the duplex bars. After rereading your article it occurs to me that some of the noise problems may be due to the poor shape of the duplex bars (they are very flattened), possibly the angle (though I have yet to measure it), and the position (a tuned duplex). My questions are: 1. Is there a method to relocating the cast duplex bars and would you recommend it? There is a small shelf in the plate forward of the existing duplex bars. Would you consider attaching an inverted V-shaped piece of something (brass?) in order to shorten the duplex segment? If so, what would you use and how would you attach it? How would you calculate the position, i.e., what should the length of the duplex be as a ratio of the speaking length? 2. Is there a method to reshaping the duplex bars (I am not pulling the plate on this particular job), or would you consider adding a small bronze half round to the top of the existing duplex which would both give a smaller radius and increase the string deflection angle? If so, do you still adhere to a maximum deflection angle of 18-20 degrees? How would you attach the half-round? And what specific material would you use? 3. Do you think these things are likely to improve this problem, or should I be barking up another tree (pun intended)? Thanks David Love _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com
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