If you are the biggest and strongest, you do not have to sound the most - you are dangerous enough anyway.
By using the knowledge they have about what Tyrannosaurus rex looked like, researchers now also hope to learn more about how she may have sounded.
In a studio, a zoologist and a paleontologist experimented with the sound with somewhat unexpected results, as shown in The World of Science.
Birds and crocodiles
The dinosaurs' closest relatives are birds and to some extent reptiles such as crocodiles and alligators.
Maybe it's not so strange that Tyrannosaurus rex did not have such a scary sound.
With today's technology, one can reconstruct the inner ear of Tyrannosaurus rex and see which tones it could perceive most strongly.
The researchers believe that this can teach us more about what sounds it itself made, because the dinosaurs must have been able to communicate with each other.
Infrasound
In the reconstruction, it was seen that the inner ear may have been particularly sensitive to very low sounds.
Maybe so low that we humans had not even been able to hear them - so-called infrasound.
Man can only perceive infrasound in the form of vibrations and then the sound level must be very high.
Creepy sounds
These results show that the Tyrannosaurus rex probably did not make any powerful roars, but it was mostly an eerie, rumbling sound.
- It sounds almost a bit messy, but you probably have to be able to feel the sound in the ground as well, not just hear.
It's like watching a rock concert on TV.
There will be no feeling, says Lars Werdelin, professor of paleontology at the Swedish Museum of Natural History in Stockholm.
He says we will never know how the Tyrannosaurus rex actually sounded, but it is possible that it could also be a light beep.
- When crocodiles lure their cubs, they make a cute little chirping sound!
Tyrannosaurus rex may have used something similar, says Lars Werdelin.
The film T-Rex unknown pages will be broadcast in Vetenskapens Värld on Monday 25 February on SVT 2 at 8 pm and on SVT Play.