Eigentone /ˈaɪɡənˌtoʊn/ — "EYE-gen-tone"
VST3 · WASM · Windows

A MIDI synthesizer that maps notes to physics-derived frequencies instead of equal temperament.

Each frequency set is built from a real physical system — hydrogen Balmer lines, planetary orbital periods, Schumann resonances of the Earth–ionosphere cavity, quantum-mechanical energy levels — scaled into the audible range by powers of two.

6frequency sets
MIDIkeyboard input
$39one-time

Run the synth in your browser.

The same C++17 DSP core as the VST3 plugin, compiled to WebAssembly and run in an AudioWorklet. 8 voices, sample-accurate, no server involvement after the page loads.

Audio starts on click. ESC to exit.
Want the VST3 before launch? Apply for beta access →

Six physical systems, one MIDI keyboard.

Every set follows the same rule: faudio = fphysical × 2N. The physical frequency is multiplied or divided by powers of 2 until it lands in the audible range. The integer N is fixed per set; the ratios between notes are preserved exactly.

H
1/λ = RH(1/2² − 1/n²)

Hydrogen Balmer Series

Visible emission lines of atomic hydrogen — H‑α (656.3 nm), H‑β, H‑γ, H‑δ. Optical frequencies on the order of 1014 Hz, divided down by 240.

Details →
Ω
fn ≈ c / 2πR · √(n(n+1))

Schumann Resonances

Standing electromagnetic waves in the Earth–ionosphere cavity. Modes 1–7 measured at 7.83, 14.3, 20.8, 27.3, 33.8, 39.0, 45.0 Hz. Multiplied by 22 (×4) so SR1 lands at 31.32 Hz.

Details →
faudio = (1 / Torbit) × 2N

Planetary Orbital Frequencies

Orbital periods of the eight planets converted to frequency and scaled up. Earth year ≈ 136.1 Hz (Cousto's "cosmic octave" reference, near C♯ in 12-TET).

Details →
ψ
En = ℏω(n + ½)

Quantum Harmonic Oscillator

Linear ladder of energy eigenvalues. Transitions are integer multiples of ω, so the resulting tuning is harmonically pure — no inharmonicity.

Details →
V
V(r) = De(1 − e−a(r−re)

Morse Potential

Anharmonic oscillator for a diatomic bond. Energy spacings shrink as n increases and converge on the dissociation limit De — keys above that point are silent.

Details →
En = n²π²ℏ² / 2mL²

Particle in a Box

Infinite square well. Energies grow as n2, so frequency intervals widen with every step — the opposite of equal temperament's logarithmic spacing.

Details →

Pricing.

Both tiers ship every frequency set, every waveform, every filter — same DSP. Free caps cumulative play time at 20 minutes per 24 hours and runs in the browser only. The $39 license removes the cap and unlocks the VST3 plugin.

Free
$0
no account required
  • All 6 frequency sets
  • Full DSP, identical to the VST3
  • Browser-only
  • 20 minutes of play per 24 hours
  • No VST3 plugin access
Try in browser
PRO
Pro
$39
one-time payment
  • Unlimited browser play
  • VST3 plugin (Windows)
  • All 6 frequency sets
  • License covers 3 machines
  • Direct email support
Buy Eigentone — $39
Educators: Pro is free for verified teachers and university courses. Email from an institutional address to [email protected] and we'll issue a license.