The archtops tend to have a brighter sound than the flattops do. In his article “The Earl Scruggs Gibson Banjo,” Doug Hutchens wrote:

The tonering in the early Scruggs model banjos was indeed a Stewart-MacDonald ring. The problem with those banjos was with the setup! The Stewart-MacDonald tonering is an excellent ring, and I'd still rather have it than most on the market today. Some banjo "critics" didn't like the Stewart-MacDonald ring. I've found one thing in my 30 or so years in dealing with banjo parts and the players. Banjo players always want whatever they can't get. There is a mystique about trying to get something that others cannot attain. And when Stewart-MacDonald rings were readily available, many thought they can't be any good. Any one could order them. (A side bar to that. Does anyone know who made the tonering for Stewart-McDonald for several years? I'll leave that for speculation, but you'll be pleasantly surprised.) (Steve Ryan, also in Ohio as is Stewart-Macdonald. - ed.)

My tone ring, complete with the correct spelling of Stewart-MacDonald, is pictured here on their site. As you can see, it's not a ball bearing tone ring. It is, as Bruce Phillips might say, good though. My banjo seems considerably heavier than most other bluegrass banjos.

      - Mark