D&D General Dragons maybe shouldn't roar.

[J-H]

They should reverberate with a deep thumping noise that you feel in your spine.
Somewhat more scary in some ways.

 

[Dioltach]

Brown noise, perhaps that's what causes dragonfear?

 

[Bill Zebub]

If you've ever heard a male lion roar on the savannah in person, it's...spooky. It's not at all what I expected. The MGM thing isn't even close.

 

[Baldurs_Underdark]

If you want to go scientific about these fantasy creatures, allow me to add my 2 cents.

You seem to assume all cavities and lungs are filled with air. But with the dragons of D&D this might not be true? The moment they start roaring, the next thing may be a breath-weapon so all the pipes might be full of fuel (fire), acid or poison. In all cases, it is likely that these molecules are much larger than air, meaning the sound is even lower. Dragons that have a cold or electric breath weapon - well, I don't even know how that works in the first place.

Here's my point about gas heavier than air:

 

[Larnievc]

“As you whirl around, your sword ready, the huge, red, fire-breathing dragon swoops toward you with a ROAR!”

See? Dragons roar.

 

[MNblockhead]

Well, they can talk...in multiple languages. In my imagination they have incredibly sophisticated vocalization.

 

[DND_Reborn]

Yes, a dragon are not a T-Rex and I doubt they are closely related. A dragon's physiology would be completely different.

So, while I found the videos interesting, especially concerning the T-Rex, dragon's will continue to roar in my games.

Attached is a sound I like myself...