# The King's Chamber acoustics: why the Great Pyramid's granite room rings

**The King's Chamber is the granite room at the heart of the Great Pyramid of Giza, and it is famous for its long, humming resonance.** It is a box of polished red granite about 10.47 m long, 5.23 m wide and 5.8 m high, a 2:1 "double square" floor, with a lidless granite box, the **coffer**, near its west wall. Hum or chant inside and the room answers with a strong, low drone.

## Why does the King's Chamber resonate so strongly?

- **Hard, parallel surfaces.** Granite reflects almost all sound, so energy dies away slowly and low notes ring for seconds.
- **Simple proportions.** A rectangular room has **room modes**, frequencies whose wavelength fits the room exactly. In a 2:1 room many of these modes line up at related frequencies, so certain notes are strongly reinforced. With the room's length of about 10.47 m, the lowest length mode sits near 16 Hz, and the first modes that stand out to the ear fall in the 30 to 120 Hz range.
- **The coffer.** The granite coffer is a resonator of its own. Struck or sung into, it rings with a clear low tone; 117 Hz is the value most often quoted for it, and leaning into it or sitting in it couples the voice to that ring.

## The shafts and the room around the chamber

Two narrow shafts lead from the north and south walls towards the outside, and five relieving chambers stacked above the ceiling spread the weight of the pyramid. Both change how sound behaves at very low frequencies. Researchers and sound healers have recorded the chamber many times; it is a favourite place to tone, chant and play singing bowls.

## Is the King's Chamber acoustics a proven healing effect?

No. The room's resonance is a measurable physical effect; claims that it was designed to heal or to alter consciousness are traditions and speculation. Many people do find the sound deeply moving, and it is a powerful space for music and meditation.

## How to use the King's Chamber as a reverb

[King's Chamber](/products/kingschamber) is a reverb plug-in (VST3, AU, Standalone for macOS) built from a model of the room: its size and 2:1 shape, its granite, the coffer with its ring near 117 Hz, the shafts and the room modes. You place the listener and the sound source on a plan of the chamber, for example inside the coffer, and hear the room from there. It can play the room as an instrument with Chant and Drone modes driven by MIDI, show its standing-wave map, and output stereo or binaural. 44 €, free for 14 days. See the [King's Chamber manual](/manual/kingschamber).