• Heavy Machine Shop

    Thomas Edison

    National Historical Park New Jersey

Talking Doll Record: Hear the Audio

 
The record groove surface viewed under a microscope.

The record groove surface viewed under a microscope.  The nearly uniform groove width shows Edison's early square "chisel-cut" recording technique, used prior to August 1889. 

National Park Service

Specifications of the tin cylinder phonograph record:

  • Estimated original outer diameter (if not misshaped): ~60.4 mm (~2-3/8 inch)
  • Estimated original inner diameter (if not misshaped): ~53.7 mm (~2-1/8 inch)
  • Width: ~ 11.4 mm (~7/16 inch)
  • Thickness: ~ 3.4 mm (~1/8 inch)
  • Groove threads per inch: 50
  • Groove type: Vertical cut, nearly uniform groove width.
  • Recording/playback speed: Unknown. (The playback speed/pitch of the recording as presented here was set by ear.)

Return to "Early Talking Doll Recording Discovered" page.

Did You Know?

Thomas and Mina Edison with Madeleine, Charles and Theodore.

Did you know that Thomas Edison had six children? Marion, Thomas Jr., whom Thomas called Dot and Dash after his telegraph work, and William Leslie, from his first marriage to Mary Stillwell. Madeleine, Charles, and Theodore from his second marriage to Mina Miller. More...