OttoAnna is a free atlas of sound. It brings together recordings of animals, places, instruments and machines with clear, practical reference pages about how sound works – frequencies, decibels, notes, hearing and acoustics – and free tools you can use in your browser.
What you will find here
- Animal sounds – birds, mammals, frogs and insects, with recordings from Wikimedia Commons, xeno-canto contributors and the US National Park Service.
- Field recordings – geotagged soundscapes from cities and wild places, contributed to radio aporee ::: maps.
- Instruments and music genres – how they sound, where they come from and how they relate.
- Reference pages for frequencies, notes, decibel levels, everyday noise, the speed of sound and hearing ranges.
- Free tools and guides written by our editors.
How the atlas is made
We build OttoAnna from open data. Facts come from structured sources such as Wikidata and GeoNames; short definitions are quoted from Wikipedia with attribution; recordings are embedded from their original archives under public-domain or Creative Commons licenses, and every page credits its sources. Reference pages are computed from physics formulas and published guidelines (NIOSH, OSHA, WHO). Pages are generated from templates that we write and review, and we improve them continuously. If you spot an error, please tell us.
Health-related pages (noise and hearing) are general information, not medical advice.
About the name
From 2004 the domain ottoanna.com was home to OttoannA, a Paris-based duo of sonic interventions and field recording formed by Rodolphe Alexis and Valérie Vivancos. This atlas is a new, independent project and is not affiliated with the duo; we took over the domain because we share its subject – listening to the world – and we hope this site honours that spirit.