Electro-Voice manufactures or has manufactured the following equipment (click to expand models list):Cables
Robert Graham (January 2002): Both the Ionovac and Ionofane (excellent tweeters) were preceded by an earlier version made by Electro-Voice, on license from DuKane, I believe. At that time (the mid to late '50's) Electro-Voice was one of the more popular home loudspeaker companies, along with Jensen, Wharfedale, University, and others. The E-V version, called the T-3500, was somewhat unreliable, but it was E-V, I think, who produced the cast aluminum horn still used by DuKane. Pictures of the E-V unit show their logo placed on the upper part of the horn flare, which you can still see in the DuKane and Fane company pictures as the circle just near the edge of the horn. If I can find a schematic of the Ionovac I'll send it in.
Jim Kovosi (February 3, 2010): If you are still looking for a schematic for the Ionovac try this link from electrovoice product archives.