• 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?