Whales and orcas is humpback whale and orca sounds heard through a hydrophone at Skjervøy, Troms, Norway. The audio is raiden04's spatial rendering of hydrophone data by Rychen et al. (2023), © ETH Zürich, CC BY 4.0. Its entry on greensound holds no recording date, so none is shown.
Who made this audio?
raiden04 did the rendering. Its Freesound page calls it a "spatial audio recording for headphone playback of songs and calls of Humpback whales and Orcas," and says the recordings are based on a data publication by Rychen et al. (2023), with the copyright line "© ETH Zürich 2023, CC BY 4.0." That publication is a dataset on Zenodo by Jörg Rychen, Alexander Eckerle, Xintong Liu and Stefan Schucker. The data's authors are not the uploader, so greensound prints two credits: raiden04, and the data's © ETH Zürich 2023, CC BY 4.0 (Rychen et al. 2023).
What did the researchers record?
The dataset describes underwater acoustic recordings from an expedition called Orcalize, held at Skjervøy in northern Norway. In its words, the data contains "vocalizations from killer whales and songs from humpback whales." The researchers recorded with calibrated hydrophones, arranged in a compact tetrahedral array that they deployed overboard from a motorboat. It lists 16 files of continuous recordings, with durations from several minutes to over an hour. raiden04's page says orcas where the dataset says killer whales.
Why does greensound show no recording date?
The Freesound upload states none. It shows April 8, 2025, which is the day raiden04 uploaded the file, not a recording date. greensound's entry for this sound holds no recording date, so neither this page nor the mixer's info panel prints one. We would rather say so than guess.
Is it looped?
Yes. raiden04's file runs 6 minutes 54 seconds on Freesound. What plays is a loop of twenty to forty seconds cut from it, with a 2-second equal-power crossfade baked into the seam so it can't click. The loop is turned up or down by one fixed amount to match the other sounds, and a limiter softens any rare loud peak. That limiter works at four times the file's sample rate, so its ceiling sits close to the true peak between samples, not only the samples themselves. Hydrophone recordings stayed out of greensound until one passed by ear. This one did: greensound's owner heard the final file and kept it.
Should I listen with headphones?
raiden04 describes it as a spatial audio recording for headphone playback. The mixer plays it through whatever speaker or headphones you already have, at the level its slider sets, like any other sound. CC BY 4.0 asks us to say what was changed, and the list under "Where the sound comes from" does: greensound cut it to a loop, matched its level and softened any rare loud peaks.