<blockquote style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;" class="gmail_quote">and also to avoid excessive stress-relaxation due to creep of the steel. </blockquote> Wow, how do you find this stuff, and why hasn't anyone presented it to Ron N and his camp before? <blockquote style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;" class="gmail_quote"> Does anyone see any fault in principle with the apparatus?</blockquote><div> The only possible issue I can think of is whether the measurement device (the dial gauge) will be sensitive enough to detect the small amount of movement we are talking about. If indeed the string is stretching far enough to be acoustically significant, but not enough to register on the dial, the test would end up giving a false negative. You may want to make the needle longer for more precision... [kurt] </div>