I have been following posts by John Colombo about sound in n-scale locomotives. Most recently, he elected to replace the decoder in a dcc locomotive that came with factory sound. He commented it was an evening project for him. If the B'mann 2-8-4 runs wells and looks good, modification even decoder replacement may be an option for some. It is at least a place to start for those of us who do not kitbash or scratch built steam.
