List: "Exactly right William, thank you. Johnathan, when you hear a string that sounds like something you would typically seat, try this. Place a screwdriver tip against the speaking length bridge pin of that string, and apply a bit of pressure to the side of the pin opposite the string. Odds are, the sound will clean up as if you'd seated the string. Take the screwdriver away and the noise returns. Replace the screwdriver, and the sound cleans up again. Ask yourself why that is, when you haven't seated the string at all." I'd suggest folks go a couple steps further with this advice. Ask yourself why if you increase pressure on the screwdriver the beat starts up again. Also actually count and write down which strings have false beats and which of these actually reacts to the screwdriver. Then figure your percentages. The real odds are that the percentages are somewhat more a game of bingo then anything else. More importantly, when you are done identifying all the strings that react to the screwdriver trick and have written down each note and string, go back through and remove each of them one at a time and check to see whether the conditions given to explain both the false beat and the fact that the screwdriver trick works are present. If this explanation was correct then in nearly every (if not all) instance you should find 1:) a loose pin, and 2:) a deepened string mark that effectively places the notch behind the pin If you actually do this, as I have on several restringing jobs to date, you will find somewhat less then half of the pins are actually loose, and that the string mark factor shows up even less often. Since the above quote is a leading into the loose pin / false beat proposition again, we might as well go there right off and get it done with. Complete your researcher's ensemble by proceeding to add CA or epoxy to your pins. Add it to ALL the pins. When done re-identify all individual strings that show false beats. What you will find is a general improvement of significant degree. But closer examination of your data will indicate there is some other casual effect at work. The data shows that 1:) far from all of the original false strings are cured. 2:) some amount of the uncured are improved. 3:) there is a significant degree of new falseness on strings that were clean originally. All this can lead you to try several different experiments in an attempt to better understand false beats. And in the end you will still lack anything close to the definitive answer. My experience shows clearly to me that a string is just as likely to display false beats (of the sort that reacts to the screwdriver) with the above conditions as without. Loose pins can be downright wobbly in there holes with the string propped up with a center pin under the strings 2-3 mm behind the pin and still there is no significant degree of assurance that a false beat will or wont appear. Try it on 20 or so strings on the next beater you get in your shop. On the other hand pins that are tight as you can ever expect them to be can also display this same kind of beat. There is just plain too much randomness to the occurrence of false beats if the loose pin/crushed edge explanation is applied. What we do know (because the rest is pure conjecture) is that the introduction of CA or epoxy significantly improves the situation. Even more so then replacing with larger pins by accounts I've heard here. So add the stuff and be glad for the improvement. But as far as I can see we have not arrived at an explanation for false beats. Cheers RicB -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20060909/51fe3b98/attachment.html
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