fiddle set up for optimum harmonics

A few years back, maybe ’07, someone, definitely a knowledgeable Brit and a fiddler (Ceolachen comes to mind) presented info regarding the proportion of the distance from the end of the fingerboard to the bridge vis a vis that from the bridge to the contact point of the tailpiece. I noted it and immediately reset my fiddles using that formula, to their greater benefit. I cannot find it in my notebooks and ask if he could please reiterate it -- that is if he’s not in banishment for his somewhat trenchant commentaries -- which I always thought were spot on although perhaps a bit strongly phrased. Thank you in advance from a Yank.

Don’t know about ratios, but traditionally the starting point is an afterlength of about 55mm. From there you bow the afterlength of the D string, and tune it to A (an octave above the harmonic at the 4th finger position, or use an electronic tuner). On most fiddles that will give you the optimum, but you can use the afterlength to adjust the sound a bit - moving the tailpiece South will give the fiddle more balls, moving it North makes it sweeter, but quieter.

The ratio is 6:1

That will work if you are using gut strings, coming straight off the tailpiece - D to a’ is 2 octaves and a fifth, so the frequency/length ratio is 6:1. But there is a problem if you use ball ended strings - the way the ball is tied and whipped means that the string in the afterlength is heavier than the main string, so to get it tuned to the harmonic it needs to be shorter.

Re: misbehaving top E on fiddle
https://thesession.org/discussions/16053#comment332958
https://thesession.org/discussions/16053#comment332981
Posted by Trevor Jennings on December 9th, 2007

A big Thank you to ‘Na eisc’ for pointing out the previous discussions on this topic. Oddly, it was my E string on a fine, old German violin that was giving me fits (a bit raw & unsympathetic). I found the postings of ‘Trevor Jennings’ and ‘Mark M’ to be just the stuff I was looking for. Thanks again friend.