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This study evaluates end-correction behavior in flue organ pipes by comparing two models: the classical low-frequency expression of Levine and Schwinger and the empirical, frequency-dependent refinement of Davies et al. [Journal of Sound Vibration 72 (1980) 543–546], later revisited by Moore et al. [JASA Express Letters 3 (2023) 055002]. Using a Microflown probe, we performed high-resolution pressure measurements inside and outside circular and square pipes to capture the transition from standing-wave to radiating behavior. Sinusoidal variation within the end-correction region and 1/rdecay beyond were observed, consistent with theory. A two-region curve-fitting approach quantified each model’s accuracy. In the tested range (0.049 ≤ ka ≤ 0.377), both models reproduced the data with nearly identical accuracy (R² ≥ 0.997), with only a slight advantage for the classical form in one square-pipe case. Probe interference was evaluated and found negligible. While the analysis employs fixed end-correction values rather than a universal fit, it provides a controlled test of how well existing models capture the spatial pressure field near the pipe termination. Results indicate that both models are adequate in this regime, and that the radiating field beyondδfollows a robust 1/rdecay independent of model choice. 

Accurate measurement of note-to-note transitions is essential for analyzing articulation in clarinet performance. Traditional methods rely on either subjective amplitude thresholds—such as the time between 5% and 95% RMS levels—or direct measurement of tongue-reed contact time using reed-mounted sensors. These approaches are limited by their dependence on user-defined parameters or invasive hardware. This study proposes a computational alternative: ΔT, a curvature-based metric defined as the time interval between surrounding minima in the second derivative of the mouthpiece pressure envelope. Using data from a sensor-equipped mouthpiece (SEM), we compare ΔT to both threshold-based timing (Tt) and tongue contact duration (Tc) across portato and staccato articulations. Our findings show that ΔT closely tracks both Tt and Tc in structured articulations, with minimal absolute difference and robust repeatability. These results support the use of ΔT as a non-invasive, objective, and reliable estimate of transition duration, enabling broader application in performance analysis, pedagogy, and real-time feedback systems. This research was funded by: National Science Foundation Grant 2109932.