Engelbart's now-famous multimedia 1968 Fall Joint Computer Conference Presentation in San Francisco, CA. The 90-minute multimedia presentation of NLS demonsted key features of the system. This was the world debut of the mouse, hypermedia, and on-screen video teleconferencing.

From the presentation

.au 11.127 khz 16 bits mono with µLaw 2;1 compression.

Originally recorded on an Apple Macintosh PowerBook using a SONY ECM-T145 condenser microphone and Adobe Premiere audio/video editing software. The original recording was saved as a QuickTime file at 22 mhz, 16 bits with no compression.
Due to Doug's characteristically low voice it was then imported into a Premiere project where the volume was raised in the project timeline three times (no filter) and saved as a QuickTime movie.
The document was then finally imported into Apple's QuickTime Player and exported as .au at 11.127 khz, 16 bits mono with µLaw 2;1 compression resulting in the version playing here.