Edison 52000 series Diamond Disc. Electric?

[Marc Hildebrant]

Uncle Vanya,

Thanks for the info on the Edison recording system. Do you have a reference for more info ?

Marc

[Uncle Vanya]

Uncle Vanya,

Thanks for the info on the Edison recording system. Do you have a reference for more info ?

Marc

Yes. The license and lease agreements all still exist at the Edison National Historic Site, though they are not now available for view. A "Historian" back in the 1990's spoiled the Edison collection for all of us by stealing thousands of documents and signatures. The collection is being digitized as quickly as the NPS can afford, but it will be years yet before the 1927 Electric recording paperwork is again made avalaible to researchers.

About thirty years ago I purchased the personal library of Mackenzie Cottrell, an engineer with General Electric who was involved of the electric recording program. Largely technical publications such as the Bell System Technical Journal, Radio Engineering, and The Journal of the Acoustical Society of America. Many marginal notes and sheets of steno paper give little insights into the various bits of the process. For example, a notation involving the improvement to the initially awful Brunswick Electric recording system: "Corrected int. dist. (intermodulation Distortion, I think), rebuild amp- 203 increase pl v from 450-1350." This suggests that the intial amplifier used a UX210, with 450 on the plate (1.25W RMS @ 5%THD) with a "Fifty Watter", a UV-203 with 1350 volts on the plate (10W RMS @ 5%THD, much more head room).