Small river is a real recording of a stream of water at Serrinha do Alambari, in the state of Rio de Janeiro, Brazil. Felix Blume made it and released it under CC0. His page states its GPS position but no recording date. Play it as river sounds for sleep; a timer fades it out.
Where is Serrinha do Alambari?
In Brazil, in the state of Rio de Janeiro. Felix Blume's description reads "Small river of Serrinha do Alambari in Brazil (state of Rio de Janeiro)," and gives a GPS position, -22.391557, -44.551898. Freesound's map pin reads "Resende, Rio de Janeiro, Brazil."
Why does it have no recording date?
The Freesound page shows January 31, 2020, which is the day the file was uploaded, not the day it was recorded. The description gives a position and the equipment but no recording date, so greensound's entry holds none, and neither this page nor the mixer's info panel shows one. We would rather leave the date out than guess it.
What does its source say it is?
Its Freesound title is "Stream of water in a small river," and its tags include stream, flow, flows and waterflow. greensound says no more than that about how it sounds, because the source doesn't.
How was it recorded?
His page says "Recorded by a MS Setup Schoeps CCM41+CCM8 on a SoundDevices 633 Recorder," and that the original recording is a 96 kHz, 24-bit WAV. Freesound lists the file at just over five minutes.
Is it looped?
Yes. What plays is a loop of twenty to forty seconds cut from that recording, with a 2-second equal-power crossfade baked into the seam so it can't click. The window is chosen to be steady: none of its quarter-seconds is more than 10 dB, about twice as loud, above the window's median. The loop is then turned up or down by one fixed amount to match the other sounds, and any rare loud peak is softened. greensound's owner listened to a preview of the loop and kept it.
Where the sound comes from
Listen safely
This is a sound, played back through whatever speaker or headphones you already own. It doesn't diagnose, measure, or promise anything about how you sleep, focus, or feel — it's just noise and a handful of real recordings, mixed the way you like them.
Keep the volume low enough that you'd still notice a smoke alarm, a phone ringing, or someone at the door. If you fall asleep in headphones, choose a volume and a pair you'd be comfortable wearing all night, and a session length that ends when you'd want the sound to stop.
If you use this near a baby, keep the speaker several feet from the crib, never inside or clipped to it, and keep the volume low — the same care you'd take with any sound machine in a nursery.
If your relationship with sound, or with sleep, feels difficult rather than simply restless, a doctor or audiologist is the right person to talk to. This is a mixer, not a clinician.
Is this a real recording or a synthesized sound?
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Real. Nothing in it is synthesized. What plays is a loop cut from Felix Blume's original recording, with its level matched to the other sounds.
Is it a stream or a river?
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Its source uses both words. The title is "Stream of water in a small river," and the description says "Small river of Serrinha do Alambari." greensound calls it small river and says no more about its size than the source does.
Who recorded it, and is it public domain?
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Felix Blume, who released it under CC0. Its Freesound page says you can copy, modify, distribute and perform the sound, even for commercial purposes, without asking permission. We credit him anyway, and the link under "Where the sound comes from" goes to the original upload.
Is this sound free?
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Yes, fifteen minutes at a time. Any one sound on greensound, this one included, is free to play for fifteen minutes, with a fade at the end; press play again whenever you like. Pro adds the full mixes, layering and longer timers.
Can I play it alongside other sounds?
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With Pro, yes, by hand. No ready-made mix opens on it: Sleep opens on night wetland, Focus on jungle rain and Relax on beach waves. The mixer supports up to six sounds at once, so you can add small river to a mix you build yourself. Without Pro, one sound plays at a time.