VectorSTEM • Featured Research Project

The Cello as a Complex Wave System

Feature Extraction, Phase Space, and Stability Transitions

This page presents the completed main manuscript of the cello wave-system project, together with its analytical companion text, foundational project files, and visual figures. The project investigates the cello as a controllable prototype of a coupled wave system through acoustics, spectral structure, feature-space geometry, and stability transitions.

Featured paper
Completed main manuscript with physically grounded feature extraction, PCA-based phase-space analysis, curvature-based transition detection, and qualitative validation on real cello recordings.
Acoustics Waves Physics Modeling Phase Space Research
Main manuscript
Full paper presenting the central framework, results, and conclusion of the project.
Pipeline B
Real cello recordings used for qualitative validation of the synthetic model.
Transition detection
Curvature-based identification of the stability transition in reduced feature space.
Companion text
Extended analytical background, physical interpretation, and broader context.

Main research texts

Main Research Paper
Completed manuscript presenting a coupled-wave framework for cello acoustics through physically motivated feature extraction, reduced phase-space analysis, and stability-transition detection, with validation on real cello recordings.
Analytical Companion Paper
Extended analytical companion to the main manuscript, providing deeper theoretical background, physical interpretation, and broader cross-disciplinary context for the cello wave-system framework.

Core figures from the paper

Figure 1 — PCA: Three Bowed String Instruments
PCA projection of violin, cello, and double bass, together with the scree plot.
Figure 1 PCA Three Bowed String Instruments
Figure 2 — Cello Regime Space and Stability Trajectory
Regime clustering for stable, harsh, and near-breaking sound, with the continuous stability trajectory.
Figure 2 Cello Regime Space and Stability Trajectory
Figure 3 — PCA Loadings: Physical Interpretation
Loading structure for instrument classification and cello-regime discrimination.
Figure 3 PCA Loadings Physical Interpretation
Figure 4 — Trajectory Curvature
Curvature-based localisation of the stability transition in reduced phase space.
Figure 4 Trajectory Curvature
Figure 5 — Relative Harmonic Amplitude Profiles
Relative harmonic profiles for violin, cello, and double bass.
Figure 5 Relative Harmonic Amplitude Profiles

Validation figures: real cello recordings

Figure A — Real Cello Recordings: Waveforms
Quasi-stationary waveform segments for light, medium, and heavy bow pressure.
Figure A Real Cello Recordings Waveforms
Figure B — Real Cello: Power Spectra and Harmonic Profiles
Overlaid power spectra and harmonic profiles extracted from the real recordings.
Figure B Real Cello Power Spectra and Harmonic Profiles
Figure C — Pipeline A vs Pipeline B
Comparison of key features between the synthetic model and real cello recordings.
Figure C Pipeline A vs Pipeline B Feature Comparison

Project development files

Pilot Research PDF
Introductory project overview and first research presentation.
Part 1 — Bow Physics
Physical foundations of bowed-string motion, including stick-slip interaction, Helmholtz motion, and the governing wave model.
Part 2 — Feature Vector
Construction of the feature space: from acoustic signal to physically motivated spectral descriptors and state representation.
Part 3 — Phase Space
Reduced feature-space geometry, clustering structure, and curvature-based detection of regime transitions.
Part 4 — Transferability
Discussion of how the framework may extend beyond musical acoustics to other nonlinear and coupled wave systems.