What does it take to create some of the most sought-after sound libraries in the world? That’s the question sound designer Greg Lester set out to answer in his new feature-length documentary about the making of field recordist Mattia Cellotto’s Animal Hyperrealism Vol. IV – the latest chapter in Cellotto’s acclaimed series of ultrasonic animal sound effects libraries. And to celebrate the premiere, Mattia Cellotto is giving away free sounds from the library.
To create this ambitious release, Mattia Cellotto spent nearly two years traveling to 20 locations across eight countries, capturing more than 2,000 recordings for the final collection.
His sound libraries are among the most popular on asoundeffect.com, the world’s largest marketplace for independent sound effects – and are known for their extraordinary detail and clarity. Many of his recordings capture ultrasonic frequencies at extremely high sample rates, giving film and game sound designers extra flexibility when pitching or processing the material, as those hidden harmonics are brought down into the audible range.
In the documentary, Greg Lester joins Cellotto on a recording trip to Denmark as he captures rare animal sounds – including hippos – and later visits him in Sweden to see how those raw recordings are edited, mixed, and shaped into the finished library.
To support the release of the documentary, a documentary hub has been set up at asoundeffect.com/animaldoc, featuring both the full sound library as well as free samples.
Animal Hyperrealism Vol. IV includes recordings of hippos, hyenas, vultures, dwarf mongooses, elephants, African cranes, parrots, tigers, pygmy hippos, rhea ostriches, brown bears, pheasants, wildebeests, African wild dogs, and many more.

