Acoustic Analysis of Used Tuning Forks

Abstract

OBJECTIVE:In this study, we evaluated used aluminum tuning forks (TFs) for fundamental frequencies (FF), overtones, and decay times. MATERIALS and METHODS:In total, 15 used (1 C1, 11 C2, and 3 C3) and 1 unused (C2) TFs were tuned, and the recorded sound data were analyzed using the Praat sound analysis program. RESULTS:It was found that FFs of the recorded sounds produced by the used C2-TFs presented a high variability from 0.19% to 74.15% from the assumed FFs, whereas this rate was smaller (1.49%) in the used C3-TFs. Further, decay times of the used C2-TFs varied from 5.41 to 40.97 s. CONCLUSION:This study, as the first of its kind in the literature, reported that some of the used aluminum TFs lost their physical properties that are important for clinical TF tests. It could be said that this is a phenomenon related to metal fatigue, which is common in aluminum products due to the cyclic load.

Diagnostic Accuracy of Tuning Fork Tests for Hearing Loss: A Systematic Review

“…31 Heavier materials have more sustained sound levels, and aluminum forks undergo metal fatigue, producing shorter decay times and performance deterioration over time. 32…”

“…A study that did not meet inclusion criteria (results of all fork frequencies were combined) reported greater accuracy with magnesium alloy forks over steel forks 31 . Heavier materials have more sustained sound levels, and aluminum forks undergo metal fatigue, producing shorter decay times and performance deterioration over time 32 …”

“…31 Heavier materials have more sustained sound levels, and aluminum forks undergo metal fatigue, producing shorter decay times and performance deterioration over time. 32 Clinicians should also be aware that TFT accuracy differed according to the clinical population under consideration. Included studies varied in case mix, hearing loss prevalence, and severity, which would result in spectrum effects-meaning differences in accuracy when tests are applied to distinct subgroups.…”

Effect of Striking Styles and Placement Angle on the Acoustic Characteristics of Tuning Forks

“…5 As a result, their fundamental frequency and decay times show differences up to approximately 74% and 41%, respectively. 7 Besides, Butskiy, Ng, Hodgson and Nunez published objective data supporting the classic recommendation about placingthe TFs parallel (PA) to the external ear canal (through the vibrating tinesof the fork), compared with the perpendicular (PE) placement. 8,9 They found that PA placement results in a higher sound energy at the level of the tympanic membrane.…”