1906 Lee De Forest Triode Vacuum Tube

Sep 1, 2006 2:32 PM

Polls


Mix Regional

The Mix Regional section for Mix's July 2014 issue focuses on Atlanta. Send us your studio news: updates, sessions, new rooms, club performances and installations. Let the Mix audience know what is going on! Send photos and descriptions to mixeditorial@nbmedia.com.

If audio would have followed the course of every other technology, then vacuum tubes would have been long forgotten by now. Yet anyone who’s ever plugged into a Marshall JTM45, Fender Twin Reverb, Vox AC30, Teletronix LA-2A or any other of hundreds of classic tube devices should give a silent nod to Lee De Forest.

Born in Council Bluffs, Iowa, in 1873 and reared in Alabama, De Forest had an aptitude for science from an early age. After receiving a Ph.D. from Yale in 1899, he turned his attention to the seminal field of radio.

Seeking to create a detector for electromagnetic radiation, De Forest began by examining John Fleming’s invention of the “electronic valve” (diode), which was fairly insensitive to variances in electromagnetic radiation. By simply adding a third electrode (grid) between the cathode (filament) and the plate (anode) of a diode, the conductance of the tube proved controllable. In this case, a fairly minute signal (voltage) at the grid would result in huge changes in the plate voltage, and the first amplification device was born. De Forest referred to his triode invention as “Audion” and received U.S. patent #879,532 for his discovery in 1907.

De Forest was granted some 300 patents during his life, including Phonofilm, a 1922 method of recording synchronous sound onto film that was unable to garner any interest in the film community. Eventually, the industry adopted an optical sound-on-film system that was similar to De Forest’s, but that was years after his De Forest Phonofilm company went bankrupt.






Acceptable Use Policy
blog comments powered by Disqus

Mix Books

Modern Recording and Mixing

This 2-DVD set will show you how the best in the music industry set up a studio to make world-class records. Regardless of what gear you are using, the information you'll find here will allow you to take advantage of decades of expert knowledge. Order now $39.95

Mastering Cubase 4

Electronic Musician magazine and Thomson Course Technology PTR have joined forces again to create the second volume in their Personal Studio Series, Mastering Steinberg's Cubase(tm). Edited and produced by the staff of Electronic Musician, this special issue is not only a must-read for users of Cubase(tm) software, but it also delivers essential information for anyone recording/producing music in a personal-studio. Order now $12.95

Newsletters

MixLine

Delivered straight to your inbox every other week, MixLine takes you straight into the studio, with new product announcements, industry news, upcoming events, recent recording/post projects and much more. Click here to read the latest edition; sign up here.

MixLine Live

Delivered straight to your inbox every other week, MixLine Live takes you on the road with today's hottest tours, new sound reinforcement professional products, recent installs, industry news and much more. Click here to read the latest edition; sign up here.

[an error occurred while processing this directive]

The Wire, a virtual press conference offering postings of the latest gear and music news, direct from the source. Visit the The Wire for the latest press postings.