Ten violins, selected on the basis that their two main resonances were within a whole tone of their two open middle strings, were found to be some of the most musically desirable instruments - Amatis, Stradivaris, Guarneris and several modern ones. In marked contrast to these were all violas and cellos tested, which characteristically had their main body and cavity resonances three to four semitones above the frequencies of their two open middle strings although they still had the same separation, approximate]y a musical fifth, between these two main resonances.
We reasoned that the clue to our problem might be this placement of the two main resonances relative to the tuning of the two open middle strings. A search through many small violins and cellos, as well as large and small violas, showed enormous variation in the placement of these two resonances. We hoped to find some instrument in which even one of these resonances would approximate what we wanted for the new instruments.
In one quarter-size cello the body resonance was right for viola tuning, D 294, but the cavity resonance was too low at D 147. We bought this chubby little cello and reduced the rib height nearly 4 in. (10 cm), thereby raising the frequency of the cavity resonance to the desired G 196. When it was put back together, it looked very thin and strange with ribs only 1.5 in. (3.8 cm) high and a body length of over 20 in. (51 rm), but strung as a viola it had tone quality satisfactory beyond expectations!
An experimental small viola that I had made for Saunders proved to have its two main resonances just a semitone below the desired frequency for violin tone range. When strung as a violin, this shallow, heavy-wooded instrument had amazing power and clarity of tone throughout its range. It sounded like a violin although the quality on the two lower strings was somewhat deeper and more viola-like that the normal violin.
The next good fortune was discovery and acquisition of a set of three instruments made by the late Fred L. Dautrich of Torrington, Conn., during the 1920's and '30's. He had described them in a booklet called Bridging the Gaps in the Violin Family. [Ref 14] His vilonia, with a body length of 20 in. (51 cm) was tuned as a viola and played cello-fashion on a peg. The vilon, or tenor, which looked like a half-size cello, was tuned an octave below the violin, G-D-A-E. His vilono, or small bass, with strings tuned two octaves below the violin, filled the gap between the cello and the contrabass. These represented three of the tone ranges we had projected for the new violin family. Tests showed that their resonances lay within working range of our theory. A year of work, adjusting top and back plate wood thicknesses for desired resonance frequencies and rib heights for proper cavity resonances in each of the three instruments gave excellent results. The vilono proved to have exactly the resonance frequencies projected for the enlarged cello, or baritone. So it was moved up a notch in the series and tuned as a cello with extra long strings.
Dautrich's pioneering work had saved years of cut and try. We now had four of the new instruments in playing condition; mezzo, alto (vertical viola), tenor and baritone. I was able to add a fifth by making a soprano, using information gained from many tests on three-quarter- and half-size violins.
With five of the new instruments developed experimentally and in playing condition, we decided to explore their musical possibilities and evaluate the overall results of our hypothesis of resonance placement. In October 1961 the working group gathered at the home of Helen Rice in Stockbridge, Mass., where Saunders and his associates had, for some years, met frequently to discuss violin acoustics and play chamber music. Short pieces of music were composed for the five instruments, and the musicians gave the new family of fiddles its first workout. The consensus was that our hypothesis was working even better than we had dared to hope! Apparently the violin-type placement of the two main resonances on the two open middle strings of each instrument was enabling us to project the desirable qualities of the violin into higher and lower tone ranges.
The next step was to explore the resonances of various size basses to help in developing the small bass and the contrabass. A small three-quarter-size bass with arched top and back proved to have just about proper resonances for the small bass. With removal of its low E 41 string and the addition of a high C 131 string to bring the tuning to A-D-G-C (basses are tuned in musical fourths for ease of fingering) it fitted quite well into the series as the small bass. But as yet no prototype for the contrabass could he located. This final addition to the series was to come later.