We do not know whether T. rex can make any vocal sounds. However, if it could, it would be pretty low pitched because the larger an animal, the lower pitched its voice will be. That is why a bullfrog has a much lower pitched voice than a treefrog, and an elephant's voice is much lower pitch than a dog's bark.
There is a group of dinosaurs called hadrosaurs or duck-billed dinosaurs that have structures on their heads that are resonant chambers so they can amplify sound. Studies have shown that the sounds they produce can be pretty loud, and can probably be heard for miles around. However, the hardosaurs evolved pretty late, and they are not closely related to other well known dinosaurs such as sauropods, theropods and most bird-hipped dinosaurs, so they may well be atypical among dinosaurs in their ability to produce loud sounds.
I don't think there's any doubt that dinosaurs made loud sounds. Their closest living archosaurian relatives--crocodilians and birds, make loud sounds especially during the mating season. Bull alligators can bellow loud and be heard for miles. Birds make all kinds of sounds. The evidence for sound production is especially good in hadrosaurs, with their expanded premaxillary and nasal bones, forming crests or resonating chambers, but that doesn't mean earlier ornithopods and others, didn't make a racket. It's possible that hadrosaur crests or snouts were expanded in various ways due to the need to make diverse sounds when ornithopod/hadrosaur diversity was high, as in the Campanian. Iguanodont diversity wasn't high, hence there was no danger of mistaking a species's sound for that of a close relative. Hadrosaur crests disappeared in the latest Maastrichtian when diversity dropped precipitously.
Reptiles generally are silent. Crocodiles are silent and deadly. Baby gators can make a squeaky sound. I doubt that T-Rex needed a voice at all. But if it did, I would imagine it to be more like a crow's caw or a hawk scree than a lion's roar.
20 x the roar of a lion.
Unfortunately, we can not study a living T Rex to find out if they actually made sound like a roar or not but what can be studied is dinosaurs closest living relatives which are crocodiles and birds.
Crocodiles make sound by using their larynx a soft tissue structure in their throat that does not fossilize and seeing as all living crocodiles and alligators vocalize this way than it is likely that their common ancestor (ie dinosaurs) did too but this is just what scientists believe and nobody actually knows 100%
Birds (another living relative of dinosaurs) actually vocalize through their syrinx which is a different organ to the larynx of a crocodiles or alligators. Birds can be quite loud as well especially when mating, So it could be argued that the vocalization of the two groups evolved independently, This would mean that the last common ancestor of birds and crocodylians (which would also be an ancestor of dinosaurs and pterosaurs ) might not have been able to vocalize at all. Then again, it might just mean that dinosaurs made sounds like modern day reptiles and birds do today. Until some hard evidence is found (which is unlikely due to the sound organs in dinosaurs not being able to fossilize) than people can only go off how todays reptiles and birds make sounds.
Great question by the way.
i'm just guessing but.... PRETTY LOUD!! Y did u make one mad?? :P
How loud would it be if a dinosaur (T-Rex) were to roar in your face ?
