When someone walks on a hard floor with high heels, the sound is often loud and “sharp” because the impact converts a relatively slow body motion into a very fast force event that efficiently excites the floor and the air. The loudness is not mainly because the person is “heavy,” but because the contact mechanics create high-frequency energy and couple it well into the building.

1) The key idea: short impact time → high-frequency sound

A heel strike is an impact. In impacts, the force rises and falls very quickly (milliseconds or less). A fast event in time necessarily contains high-frequency components.

• Slow force change (gentle step) → mostly low-frequency vibration
• Very fast force change (heel “click”) → lots of mid/high-frequency energy (hundreds of Hz to several kHz)

This is why heel steps can sound like clicks or knocks: the waveform has sharp edges, and sharp edges require high frequencies.

2) High heels concentrate force into a tiny contact area

Pressure is force divided by area:$$P=\frac{F}{A}$$

A high heel has a very small contact area $A$A. For roughly the same body weight force $F$F, the pressure becomes very high. High pressure leads to:

• Less deformation area in the shoe sole (less “cushioning”)
• A stiffer contact (hard heel tip against hard floor)
• A faster force rise (higher peak force over shorter time)

All of this makes the impact “harder” acoustically and increases the high-frequency content.

3) Stiff materials store less energy as deformation and radiate more as vibration/sound

Soft materials (rubber soles, carpet, underlays) absorb energy by deforming and damping. Hard materials (wood, tile, concrete, hard plastics) do not.

So with hard heel + hard floor:

• Less energy is dissipated in the contact
• More energy goes into floor vibration
• Vibrating surfaces then radiate sound into the air

In simple terms: hard-on-hard behaves like a mallet on a drum skin (not exactly, but the same principle of efficient excitation).

4) Floors and building structures have resonances that the impact excites

A floor is not perfectly rigid. It has resonant modes (bending modes) and connections (joists, slabs, beams). A heel strike is broadband, so it can excite many resonances at once.

Result:

• Some frequencies get amplified strongly (often mid frequencies where human hearing is sensitive)
• The sound can “ring” briefly after each step

This is also why the same heels can sound very different on different floors: you are “listening to the floor system” as much as the shoe.

5) Structure-borne transmission makes it loud elsewhere

Heel impacts often become structure-borne sound:

1. Impact injects vibration into the floor.
2. Vibration travels through the structure.
3. Other surfaces (ceiling below, walls, radiators, pipes) re-radiate sound.

This is why a neighbor may hear loud footsteps even if the walker is not producing much airborne sound in the room itself.

6) Why it sounds especially “loud” to humans

Two perception reasons:

• The sound has strong components in 1–4 kHz, where human hearing is most sensitive.
• It is impulsive and repetitive, which draws attention more than steady noise.

Summary (one sentence)

High-heel footsteps are loud because the heel creates a stiff, small-area impact with a very short contact time, generating high-frequency energy that efficiently excites floor resonances and transmits through the building as structure-borne sound

---

Why a fast force change creates high frequencies (the core physics)

The time–frequency rule

High frequency means rapid variation. A signal that changes very quickly in time must contain higher-frequency components.

A simple (and very practical) rule is:$$f_{\max} \approx \frac{1}{\Delta t}$$

• $\Delta t$ = the “rise time” or characteristic duration of the force change.
• Shorter $\Delta t$→ larger $f_{\max}$fmax​ → more high-frequency content.

Example:

• If the main force change happens in $\Delta t = 10\ \text{ms}$, then $f_{\max} \sim 1/0.01 = 100\ \text{Hz}$ (mostly low-frequency).
• If $\Delta t = 1\ \text{ms}$, then $f_{\max} \sim 1/0.001 = 1000\ \text{Hz}$fmax​ (now clearly audible mid/high).
• If $\Delta t = 0.1\ \text{ms}$Δt, then $f_{\max} \sim 10\ \text{kHz}$ (very high-frequency content).

So the reason “sharp impact” produces high frequencies is simply: the force is changing extremely fast.