A scientific that name may be, it was actually a cheap method to show cartoon characters talking by imposing a recorded live mouth to their face. Clutch Cargo was most infamous for using it a lot and it probably aged the year it came out!
However, Syncro Vox was still used time and time again, albeit ironically as a gag, in other cartoons. One example is Looney Tunes: Invasion of the Bunny Snatchers where a knock-off Daffy gets “Syncro-Voxed” for only one scene.
Do you guys remember any examples of Syncro-Vox gags in other cartoons?