..This general shape shall represent any or these three type of parts: (top view)

Laying out Mode #5 Lines and finding the Acoustical Center
via the Tap Tone Method {Plates// Fingerboards// Tailpieces }

(10/2020)
page AA_33

...By David Langsather, Violin Acoustical Researcher www.violinresearch.com info@violinresearch.com

The loudest overtones tap responses...

The areas of lowest response of the higher overtone tap tones.

 Tap along horizontal paths, marking the two lowest response points, and toward the center, the highest upper overtone response point.

These are the mode # 5 nodal lines that will be used for acoustical adjustment

This line is marked where the highest high overtone is located.

Finally tap from side to side along the high overtone line already determined then and mark the location of the strongest high overtone. This point is the Acoustical Center, and it will be used in the tuning and acoustically adjusting...

When done, our 'plate' will look something like this, marked and ready for acoustical adjustment to our goal frequencies.:

Now we measure the tap tone of the three areas by tapping in the center and comparing the tap tone with our tap tone wood reference tool (see: 'useful tools'):

{The three taps usually make a progression. The usual procedure is to make all three the same and then, adjust to the overall goal frequency. If one is almost correct, then concentrate on the other two areas. }