Bob Arnold was a popular music historian and collector in Albany, California. His collection consists of his research and correspondence, and includes scrapbooks, program notes, interviews on cassette, and compilations on open reel tape drawn from his music collection. Perhaps his most successful project was about a 1930s jazz singer named Midge Williams. His tenacity resulted in bringing to light a remarkable amount of detail about Williams' life, as well as her family performing group the Williams Quartette, the Williams' history in Allensworth, California (an African-American agricultural community in Tulare County), and the manager of the Williams (and arranger/composer in his own right) Roger Segure. In 1933, Segure booked a tour of Asia for the Williams. There are playbills, contracts, catalogs, record labels and correspondence from this trip in the collection, which came to Arnold by way of Segure's widow. Arnold appeared to be in the process of assembling a book based on this research, and a few typescript chapters survive.

This collection has been processed with generous financial support from the National Historical Publications & Records Commission.