In a 2013 interview with Variety, Jurassic Park sound designer Gary Rydstrom admitted something odd. Much like the film’s plot lines relied on the use of frog DNA to create living dinosaurs, Rydstrom and his team of sound designers relied on the sounds of horses, geese, and his own Jack Russell Terrier (“Buster”) to create living dinosaur sounds.

“Every day I would see my dog playing with the rope toy and doing exactly that, pretending like he’s killing his prey,” recalls the seven-time Oscar winner for sound design and sound editing.

Rydstrom recording the sound of his dog growling and slowed it down drastically to become the foundation for the low, deep growth of the T. rex—and similarly mixed recordings of other animals (including mating sounds) for the film’s other dinosaurs.

As we just so happen to process a full library of downloadable stock animal sounds, we decided to take a stab at recreating some dinosaur sounds ourselves using stock audio clips.

Curating the sounds required a bit of finesse, especially when choosing from the more than one hundred thousand stock audio downloads AudioBlocks has to offer, and it’s important to think ahead to find sounds that are both distinct enough from each other yet are also complimentary. By choosing sounds that didn’t particularly flow together before editing, we were able to provide a full breath of sounds for high, medium, and lower frequencies. We also weren’t afraid to use the same animal more than once, as Rhydstrom himself stated that he used a horse for four animals in the making of Jurassic Park.

Once we had our sounds, we slowed them down and dropped the pitch to match the size of the mammoth beasts, while also making sure the “attack” (start) and “decay”(finish) of each multi-track was uniform across all sounds used. While it is possible to have one sound begin after another, it is difficult to keep the sounding uniform when doing so.

Distant Brachiosaur

One of the best scenes of the original Jurassic Park film is when Dr. Grant (Sam Neil) and Dr. Sattler (Laura Dern) first see the full-sized brachiosaur are filled with the same awe as the audience.

To get the drawn out wail of the giant brachiosaur, we selected stock audio clip of cow mooing, dropped its pitch by 16.26 semitones, and stretched it by 78.8%.


We then added a “distant ghost howl” sound and did the same (although not as substantially as the cow), then reversed it and got the final product.

Roaring T. rex

To mimic the roar of the T. rex, we used a little inspiration from one of our favorite movies, The Wizard of Oz, and sourced clips from goats, tigers, and bears to get the recreate the roar of a much lower beast. After substantially lowering the pitch on the goat, we tinkered around with the attack and decay until it seemed to fit.


Growling T. rex

This audio clip proved to be a bit more difficult, and we used a combination of tiger, “wounded jungle animal,” and our beloved cow stock audio for good measure. We stretched each of the sounds anywhere between 60-120% and dropped them 8-20 semitones. Since stretching the sounds made them far longer than their originals, it was also necessary to edit them to be the same length. Since we wanted to keep the integrity of the “attack” and “decay,” it was necessary to edit the lengths from the middle of the clip and stitch them back together with a series of sweeping fades and crescendos.


Images courtesy of Universal Pictures

Brian Platt writes about film, sound effects and dinosaurs for