Recent Work on Violins
Frank A. Saunders · The Journal of the Acoustical Society of America · 1953
(a) Loudness-frequency curves of violins disclose peaks caused by natural vibrations of the body and of the inner air. “Overtone peaks” occur when a natural vibration coincides with one of the partials of the tone. Shifting the frequencies of the natural vibrations is possible and can produce a more even distribution of strength. (b) The volume of tone is very sensitive to the thickness of the top plate along the line where it is attached to the rest of the body. Thinning a groove part way around the top has produced marked improvements in several instruments. (c) The air inside the box produces one noticeable peak only in the loudness curve. Tuning forks placed in front of the f-holes produce responses but they are the result of body vibrations. (d) Experiments on f-holes show that long ones are somewhat better than short, and also that the main function of the bass-bar is to carry vibrations from the active foot of the bridge to the wider areas. (e) Resonating strings reduce loudness rather than increasing it. Interesting phase differences occur between strings, or the inner air, or parts of the body. (f) A string gives more tone when the others are relaxed.