Personally I'd use an occasional guttural "Aa! Aa!" (Best I can describe it!) rather than making growling or barking noises which the puppy is more likely to think you are offering to play fight with him than anything else. Just don't over do it and make it clear the puppy isn't to continue doing whatever it is, by distracting it, and if necessary picking it up and moving it away to play with something else. If you use a crate for time out, then make it a pleasurable experience giving him a special treat or toy to chew.

Don't forget that as a breed they desperately want to please you. Have your ground rules as you would a human child, but go easy on them while they're babies - it's for such a short time. By 7 months old they're already calming down.