RingBench Pro

ACOUSTIC WORKBENCH

Measured spectrum

Review recurring peaks, mode ratios and recordings in Evidence.

Capture settings and files

Use the defaults unless capture repeatedly fails.

Trigger above noise · dB

Tone prominence · dB

Skip impact · ms

Pause between taps · ms

One tap per file, with quiet before it and at least half a second of ringing afterward.

Recorded evidence

Measured

The lowest repeatable resonance drives the initial acoustic screen. Upper tones add evidence for a fuller model fit; the band and tolerances are provisional.

All taps · detected peaks and ratios

Peak	Ratio to fundamental	Above background

Recording

Selected tap

Save each tap’s WAV separately. Measurements include matching timestamps. Peaks heard on only some taps remain visible but do not count toward the joint fit.

Geometry and material

Entered values

Mass · g

Diameter · mm

Mass measured on my scale Diameter measured with calipers

Alloy

Young’s modulus · GPa

Poisson’s ratio

Geometry constraint

Measured rim thickness · mm Rim reading measured with calipers

Plate model

Held during the test

Maximum rim width · % of radius

Maximum rim / centre thickness

Uncertainty assumptions

These bounds are exploratory inputs, not established coin tolerances. Changing them changes compatibility.

Modulus uncertainty · ±%

Density uncertainty · ±%

Mass uncertainty · ±%

Diameter uncertainty · ±%

Mass constrains the total volume. Rim thickness is not used as the thickness of the entire coin.

Geometry-family prediction

Modelled

Mode	Frequency	Ratio

Experimental concentric centre/rim model. Relief, support-induced pitch shifts and layered construction are not represented. Mode ranges below use nominal material values; the main band also propagates the stated uncertainties.

Joint peak fit

Material compatibility

Geometry uncertainty

Measured Hz	Mode	Fitted Hz	Observed ratio	Model ratio

A Pro model fit requires two distinct modes recurring across taps, one of them the lowest; a third is used when recorded. Ratio tolerance: 3% for the thin plate, 1% for the 3D solid model. A tone near a whole-number multiple of a lower tone never counts toward the two. A matching lowest frequency remains useful even when this joint fit is unresolved. Nearby split components count at most once; fit tolerances are provisional.

Playback and comparison

Modelled sound

Support model

Material Q

Comparison coin

Comparison alloy

Playback uses an illustrative member of each geometry family. For the same coin, changing alloy preserves volume and changes the modelled mass.

Playback transpose · semitones

Q and support affect synthesized decay. Transpose affects playback only.

Alternative material hypotheses

Alloy hypothesis	Model band	Joint fit

These are model comparisons, not composition identifications.