Any breed can be companions, it's the temperament of the animals that are the most important aspect.
Is your pittie friendly with other dogs? As long as she gets along well when introduced with new dogs I don't think there should be many issues.
Are you adopting the **** hound from a shelter or buying from a puppy? Puppies are pretty agreeable when it comes to meeting new dogs, but older more established dogs have their own ideas. If you're adopting from a shelter I would suggest letting the shelter know that you have another dog and request a meet and greet. If you're getting a puppy I would watch the video below on how to introduce a puppy to an older dog.
My pit is good with other dogs. She just gets overly excited and tries to immediately play running circles around them which freaks some dogs out. I am adopting him off a couple who doesn't have time for him they say he is friendly and I know they're generally friendly dogs. He is 1 my pit she is 4-5