Mustafa Obaid · Portfolio

Plate I · physical model of a stiff, damped string

Monochord

Pluck the string and listen. The spectrum shows which partials the pluck point silences, and how a stiff string stretches its partials out of tune.

String
Guitar E2 · wound steel 0.046″
f1 measured
—
f0 predicted
82.41 Hz
Inharmonicity B
—

Drag the string and let go

Drag the string vertically with a pointer and release it to pluck. With the keyboard, use the left and right arrows to move the pluck point and Enter or Space to pluck.

Spectrum

Log frequency. Lines mark the predicted partials n·f0·√(1 + Bn²); the waterfall below shows the last few seconds.

    • Live spectrum
    • Start of the note
    • Predicted partial
    • Predicted level
    • Missing partial

    Excite

    Pluck at

    String

    Material, gauge, length and tension.

    Material

    Experiments

    Stiffness and damping. Sliders re-pluck when you let go.

    A stiff string resists bending, which raises high partials more than low ones. Push B towards 10⁻² and the tone turns bell-like.

    Cents above n·f0, partials 1–20 theory measured

    Listen

    What the ear hears: the force on the bridge, or a pickup.

    Partials

    Measured from the first second after the excitation.

    n Predicted Hz Measured Hz Δ ¢ Level dB Theory dB

    Play

    Each key retunes the string's tension, T = μ(2Lf)², and plucks it. Computer keys: Z–M and Q–U.

    Plate II · notes

    How it works

    The equation, the finite-difference scheme, the validation and the limitations. Loading the typeset equations…