Kewl, this will be intersting to watch. In 1930 the resonated banjo was in its infancy, having just been developed for better volume in the radio studio around 1928. I would expect that the banjo used should be an open back version. Also lets see how much of the old time music really gets played or will it be modern day renditions of old time. I am looking forward to seeing this movie. Thanks for bringing it to our attention.