The Usage of Rubric in Evaluation of Different Properties of CellosÖzgün Demir, Ozan Evrim Tunca
Farklı Nitelikte Çelloların Değerlendirilmesinde Rubrik KullanımıÖzgün Demir, Ozan Evrim Tunca
There are a lot of new studies that can be done on this subject since there are few academic studies about the instrument than other art branches both in our country and in the World. Sound production and tonal differences between different quality instruments are also one of these research topics. The purpose of this research is to develop a tool to test different properties of a given violoncello. The properties tested are the variety of color, vibrato production, capacity of volume, equality of sound among different registers, characteristic tone. The study is designed as descriptive research. Several professors of cello and a volunteer undergraduate student have participated in the study. Handmade cellos were used for the research. The model of this research is a single scan model from general screening models. Qualitative findings have been gathered by scanning sources. In collecting these data, native and foreign books, theses, articles, reports and etc. related to the subject have been utilized. In addition, experts with over ten years of lecturing experience in conservatory have been consulted about the criteria of instrument evaluation. Quantitative data have been obtained by a string instrument rubric (YÇR). In this study which is descriptive research, instead of the universe-sample model, a study group was established in accordance with the type of research. The study group of the study consists of; three different handmade cellos, six expert lecturers on the field and a volunteer undergraduate student from Cello Arts of Music Department of Conservatory of a state university in Central Anatolia. For the research purposes, expert opinions have been taken and literature has been examined thus the evaluation criteria have been determined as the loudness of the instruments, diversity of the sound color, the equality of the sound on different strings or registers, and the vibrato production. To evaluate these criteria, appropriate pieces have been selected with field experts. Afterward, the student who would take part in research has studied the pieces individually. After this process, the student has been asked to execute his performance with three different handmade cellos. Video recording has been done in order to observe and examine the performance of the student with different instruments. The records of the students’ performance with different instruments have been evaluated comparatively by six experts from the State Conservatory Cello Arts. Experts have not been told which instrument was which, and have been asked to evaluate as “instrument 1-2-3”. In the evaluation process, the String Instrument Evaluation Form (Rubric), which had been developed by the researchers and evaluated by expert opinions, has been used to evaluate the sound characteristics of the instrument in seven criteria. Findings based on differences between performances from different instruments have been discussed by the experts. Quantitative data obtained by the String Instrument Evaluation Form have been analyzed by SPSS (Statistical Package for the Social Sciences) data processing software. Rubric, the graded scoring key, has been successfully applied in this study as an evaluation method that allows objectivity at a measurable level. By providing a scoring chart according to the success levels in the evaluated criteria, it has enabled accurate scoring. According to the obtained data, the total scores of the three cellos compared in this study has been close to each other and they have had similar results according to the experts. However, they have been separated from each other by their performances between criteria. These differences have been able to be distinguished clearly by the detailed scoring system of the Rubric. The rubric has been able to reveal the instruments with similar sound characteristics and distinguish the strengths of them. It has revealed the difference in sound characteristics between old and new instruments. The research also has shown that the rubric is a useful method to reveal the weaknesses of the instruments in order to improve them in the future.