Violin Scroll acoustical tuning (adjustment)...
( Updated: 12/2017)
..By tap tone of the Scroll, I mean a tap in this direction and all along the shape following the curves. This is measured and adjusted as one of the last items before varnishing the violin and after the neck (under the fingerboard) tap tone is adjusted to 176 HZ (same as the top plate).
...We want to adjust these tap tones to: 198 Hz (same as the back plate) using the new wood reference tap tone scale. (See useful tools in Tap Tone Technology section).
To lower the tap tone of the scroll, alternatively the throat could be made deeper. Do this in tiny steps and measure so you do not overdue!
...I imagine that getting this part of the neck structure to work properly with the rest of the neck and instrument, will make a notable imporvement in the playing characteristics of your instrument.
(c) 2017 by David Langsather
File the flutes deeper here on the bottom side of the scroll as well as on the top (opposite side) of the scroll; to lower the tap tone of the scroll.
..To raise the tap tone of the scroll; narrow the sides, throughout the scroll, or alternately:
..file both ends of the center eye (being careful to keep the ends square) to raise the tap tone. Do this carefully, as a little wood removal makes a big change.
..Tap tone taps in the center and on both sides, should all match the 198 HZ goal. The center tap will average the two outer taps. Adjust the side that is farthest off goal first, and then the other side until they match at 198 HZ.
...Carry this tuning all around the scroll shapes.
..As a check, the end tap ot the eye should be 213 Hz Tap Tone.