Frequency Laboratory (generator-frecvente)

English · Română · Français · Italiano · Español · Português · Deutsch · Magyar

Version: 3.2.2 · Last updated: 2026-11-03

Status: stable · Offline: complete

Interface languages: Română, English, Français, Italiano, Español, Português (PT), Deutsch, Magyar

Live / demo: https://chiuta.github.io/generator-frecvente/

A single-file HTML audio tool (index.html) that runs in the browser through the Web Audio API: A/B oscillators (including binaural mode), sequencer, EQ, ambient sounds, frequency presets, recording, microphone measurements and an indicative hearing test.

Informational/educational content; it does not replace medical advice. The "Solfeggio" and "Schumann" categories come from modern (New Age) traditions and have no scientific validation; no therapeutic effects are promised. The hearing test shows a relative threshold and is not a medical audiogram. Presets with names such as "release from fear" or similar have no proven medical effect. For tinnitus or hearing problems, consult an ENT doctor. Keep the volume low and use headphones with caution.

Usage

Open index.html in a modern browser (or use the version published through GitHub Pages). Press "Start" to start the sound; the shortcuts are described on the page (key ?).

Data and privacy

Verified by audit: the page makes no network requests (there is no fetch, CDN or external fonts; the fonts are embedded). The microphone is used only if you enable it explicitly, and the signal is processed locally. Settings may be kept in localStorage. The only external links are the voluntary support links and the author's website.

Limitations

Behaviour depends on the browser (Web Audio, MIDI, AudioWorklet). A newer version of the tool exists in the same portfolio: FrequencyLaboratory (the link also appears in the banner on the page).

Hearing protection and volume limiter (3.1.0)

A warning with confirmation (“I understand — enable sound”) appears at start-up: until then the audio output is muted. A volume limiter (a ceiling for all sound sent to speakers/headphones, including the hearing test) is built in: −6 dB by default, adjustable from −30 dB to 0 dB from the “LIMIT … dB” pill in the header; the limit is kept in localStorage (generator-frecvente.volcap) and the confirmation only for the session. The “Master” volume stays within the limit; recorded files (WAV) are not affected. It is not a medical device and does not guarantee hearing safety: start with the device volume at minimum.

See also: FrequencyLaboratory

Frequency Laboratory (generator-frecvente) (this app) and FrequencyLaboratory share a code base and overlap a lot. FrequencyLaboratory is the newer, more complete version (modular system, profiles, more analysis tools); this app keeps the classic single-panel interface and adds the scene library (sequences of binaural stages). The two apps have NOT been merged; they use separate storage keys (own prefix) and can pass a configuration to each other through a link (#state=). Pick FrequencyLaboratory for the full feature set and this one for scenes and a simpler layout.

History / Changelog

• 3.1.0 — 2026-10-27: hearing-protection warning with confirmation before the first sound + volume limiter (ceiling, −6 dB default, adjustable); “see also” note for FrequencyLaboratory; Status/Offline lines; CHANGELOG.md (previous: v3.0.0).
• 2.2.9 — 2026-10-23: fff-kit 1.2.0: the last native alert/confirm/prompt calls are gone: messages appear as accessible notifications (aria-live, in the interface language) and deleting a favourite by long press asks for confirmation in the kit's FFF.dialog dialog. The “Mode m / Mode n” labels are now translated in all 8 languages.
• 2.2.7 — 2026-10-22: Touch targets: the “show harmonics on spectrum” checkbox sits in a label at least 24 px high. Re-audit at 360 and 1366 px (initial state, expanded sections, hidden panels): no target under 24 px and no text under 12 px remains.

2.2.6 — 2026-10-22

• fff-kit 1.1.4: touch targets and minimum text size; touch targets/text fixed

2.2.5 — 2026-10-22

• fff-kit 1.1.2: PBKDF2 600,000 iterations, anti-clickjacking protection.

2.2.4 — 2026-10-22

own localStorage keys with the generator-frecvente. prefix, migrated automatically from the old lab_frecv_ keys (which collided with FrequencyLaboratory on the same origin: presets and theme overwrote each other); the technical label now lists the 8 interface languages; the hidden file fields are labelled in every language; visible keyboard focus; the banner link wraps on narrow screens. mobile and accessibility polish: text at least 12 px and touch targets at least 24 px.

2.2.3 — 2026-10-22

• About 50 aria-label/title attributes that were left in English (Romanian included) are now translated in all 8 languages; the default stage names (“Stage 1/4”) follow the interface language and update live when it changes.

2.2.2 — 2026-10-22

• The "theme · share" panel title is now translated in Romanian ("partajare").

• 2.1.1 — 2026-10-19: in the banner, an "Open the current configuration in FrequencyLaboratory" link (the current state in the #state= fragment, new tab; no network requests).

• 2.1.0 — 2026-10-14: Backup and data labelling (fff-kit).

• 2.0.4 — 2026-10-12: the version and the last-updated date are shown in the app

• At start-up the 6 "v2.0: …" notifications no longer appear (release notes that overlapped the interface for ~10 s, especially on mobile); only the single first-start hint remains. The notification stack is limited to 3 (the oldest is removed).

• Preset library: search field across all 6 categories (name, description, frequency; diacritic-insensitive, multiple terms), with a counter and a message for zero results; pressing a category label clears the search. CSP: script-src by SHA-256 hash, without 'unsafe-inline' (blob: remains allowed for AudioWorklet/worker).

• The content is now wrapped in <main>, the "newer version" banner is an aside, and the headings in the notes panel are h2 (correct h1 → h2 order); the metronome's BPM field has an accessible label. axe-core: 0 violations at 1280 and 360 px.

• On narrow screens (360 px) the notes panel no longer causes horizontal scrolling of the page.

• Notifications (toasts) are now a status region for screen readers.

• The version number was raised in the title, header and footer (v2.0 → v2.0.1 → v2.0.2). The newer version remains FrequencyLaboratory.

Licence

MIT, according to the header of index.html; see LICENSE.

Audit: 2026-10-10