How We Log Changes
Only meaningful changes are listed: algorithm corrections, new pages or tools, accessibility or performance improvements, and bug fixes that affect behaviour. Cosmetic copy edits and dependency bumps without user impact are not listed. Each entry is dated and grouped. No history is fabricated.
Future code changes that alter measurement semantics (e.g. weighting, Leq, calibration, time weighting) will add a dated entry here and, where relevant, re-review Methodology and Accuracy.
History
Leq energy-averaging correction, Methodology & trust architecture
2026-08-21- Corrected Leq from squared-dB averaging to true energy averaging: Leq = 10·log10(mean(10^(Li/10))) — fixes under-reporting of loud events.
- Added /methodology/ — full signal-path, Web Audio implementation, weighting and time-weighting details with SVG diagrams.
- Added /validation/ — repeatable reference protocol and honest results template (no fabricated data).
- Added /editorial-policy/ — sourcing, review, corrections, and AI-assistance disclosure.
- Added this /changelog/ page.
- Added dedicated meter pages: /noise-exposure-calculator/, /dba-meter/, /dbc-meter/, /leq-meter/, /frequency-analyzer/, /audio-spectrum-analyzer/.
- Expanded header/footer navigation, breadcrumbs, internal linking hubs, and SEO metadata across all new pages.
PDF report, exposure calculator, calibration alignment
2026-08-20- Added on-device PDF Sound Measurement Report (lazy-loaded jsPDF) — header, session info, statistics, device info, and disclaimer; alongside CSV/JSON.
- Added Safe Exposure Calculator (NIOSH 85 dB = 8 h, 3 dB exchange) in the meter dashboard and /noise-exposure/.
- Calibrate dialog now supports “Use avg” alignment (align averages, not peaks, over 30–60 s) with localStorage persistence.
- Accuracy and calibration guides expanded with conservative, device-agnostic language.
SEO and performance iteration
2026-08-19- Homepage structured for fast tool-first UX: meter above educational content, progressive disclosure for advanced controls.
- sitemap + robots.txt hardening, canonical consistency, and OG/Twitter metadata audit.
- Font loading optimization (preload + print trick), caching headers, and ambient background performance tuning for mobile.
Site build-out: meter, spectrum, guides
2026-08-18- Initial Astro 7 + Tailwind 4 implementation of the real-time decibel meter, waveform, spectrum analyzer, history, and device diagnostics.
- Core content cluster: Sound Level Guide, How to Measure, Accuracy, Calibration, dB vs dBA, Noise Exposure, Phone Decibel Meter, Learn hub, FAQ.
- Legal and privacy foundations: Privacy Policy, Terms, Disclaimer, Cookie Policy, About, Contact.
See also Methodology for the current measurement implementation and Validation for how to verify it. Questions about a specific change? Contact us.