A focus soundscape with rules, not just sliders
Ambient players give you sliders and leave you to fiddle. This one lets you say “fade in over 3 s, add the low rumble after 20 minutes, go quiet on every break, stop at 50” — and then keeps its word even if you switch tabs.
- Runs entirely in your browser
- Works offline
- No upload
- No sign-up
- No watermark
Loading the tool…
How it works
- Pick a preset or set the layers by hand; leave the spectral guard on so the highs do not pile up.
- Set the rules: session length, fade-in, pomodoro work/break, when the low rumble should arrive.
- Press Play. The whole schedule is handed to the audio engine at once, so it runs on time in the background.
Why nothing is uploaded
Every operation on this page is done by code running inside your browser tab, using the same engine that renders web pages. The file is read from disk into your tab’s memory, transformed there, and written back out as a download. It is never sent anywhere — not to us, not to a third party.
Verify it yourself
- Open your browser’s developer tools (F12) and select the Network tab.
- Load your file and run the tool.
- The only requests you will see fetch the tool’s own code — and, for a few heavy tools, their open-source engine from a public CDN — plus one small page-view ping to loreatec.jp (page address and title, nothing more). None of them carry your file.
Frequently asked questions
Where do the sounds come from?
They are synthesised live from noise: white noise shaped by filters becomes rain and a stream, brown noise swept by a slow oscillator becomes wind, a low-passed rumble plus scheduled crackles becomes the fireplace. There are no recordings and no streaming — the page has nothing to fetch, which is why it works offline and stays private.
Why does the schedule survive switching tabs?
Because the fades and breaks are written into the audio engine as timed automation when you press Play, rather than run by JavaScript timers. Browsers throttle timers in background tabs; they do not throttle audio automation. Changing the master volume mid-session rewrites only the final fade, so set the rest before starting.
What is the “spectral guard”?
When several layers are on, only the loudest keeps its high frequencies; the others are low-passed at 2.5 kHz. Stacked hiss is what makes ambient mixes tiring after an hour; keeping one clear top layer over a warm bed avoids it.
Will it sound like a real café?
No, and it does not try to. It sounds like a well-shaped noise bed — which is what masks an open office. For actual café or nature recordings you need recordings; those come with licences and megabytes this site deliberately does not ship.