No I am not trying to tell you that all dogs sound exactly the same. Where did you get that idea?
Why did you see the need to use the word exactly.... Is it because if you put two dozen Jack Russell in a group, or Chihuahua, or Akita, or... you can always find some that sound so similar, you could hardly tell the difference?
Isn't that the reason we can tell the difference between certain breeds of dog, but can't tell the difference between others?
You aren't trying to tell me differently, are you?
Wanna play a game then?
Let's play identify the dog.
Every Dog Breed Has A Distinct Bark, But You’ll Probably Never Hear The Difference
Ethologist Csaba Molnar dug deeper into our ability to recognize our own dog’s bark. His study focused on recognition of individual barks by their owners, who in this case were sheepherders who spent all day around their dogs. While most of them thought it would be simple to determine which bark belonged to their own dog, they were unable to tell the difference between their dog’s bark and that of another.
In Molnar’s study, he came to the conclusion that dogs have different types of barks that mean different things, but if one dog barks for the same reason as another dog, the two barks will sound the same. He tested this by playing different barks, and in doing so, people were able to determine which bark meant what. For example, two different dogs barking to play.
He also found that barking is a learned and evolved trait, that was potentially brought about in domesticated dogs via humans. This theory is supported by the fact that wolf pups bark, but it is not done by adults, they have no need to.