Tuning a Cable Nelson (Lyon & Healy) yesterday, I noticed something interesting about the tenor/treble bridge. Periodically, the speaking length progressions would change at every four or six unisons, so that at the change, the note above was nearly as long as the one below. This is the first one of these I have noticed out there in the world, but I recognized the pattern because I had played with it on my scaling spreadsheet a couple of years ago. It was a genuine equal tension scale, at least through the treble. The idea is that you sweep a "regular" log scale, determine wire size breaks, and adjust individual unison speaking lengths up or down from the center of each wire size section, to make the tension changes between wire sizes as smooth as possible. Of course, it screws up the corresponding inharmonicity curve, but what the heck. I've heard a lot of talk about equal tension scaling through the years, but this is the first production example where I've seen it done through the treble. In the bass, it's not necessary to change speaking lengths, and some truly strange scales are possible without looking like anything unusual. Now for the big question. Why would anyone particularly care if string tensions were the same through any particular section when it's done at the expense of the inharmonicity curve? Yea, OK, they probably didn't have the inharmonicity information we have today and were playing the cards they had, but it still seems like a strange approach. Ron N
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