First serial to include sound.
As each chapter of the "part talking" version began, it looked like a typical silent film with title cards. It was accompanied by synchronized sound effects and music recorded on large discs similar to record albums. In the middle of each chapter there are several segments where the title cards stop and a full dialog sequence commences. After a few minutes the dialog on the audio stopped and the title cards resumed - again accompanied by just music and effects. This was one of several techniques used in the late 1920's for making films that were not fully a talkie and not fully a silent either. The "sound on disc" system quickly fell out of favor for "sound on film" which provided better synchronization of the dialog with the video.
A silent and a "part talking" version of this serial were released.
A complete 10-chapter copy of the silent version of this serial is held by the UCLA Film and Television Archives.
The version which survives on home video is in fact the "part talking" version, but it is missing the original audio. A private collector is known to own a number of the original sound discs of King of the Kongo, but they have not yet (as of mid 2005) been played back, recorded, and synchronized with the video.