Part 22

Electro-Voice dynamics 645 and 650.

For this article we will take a look at two interesting modernistic Electro-Voice microphones that came out in the late 40s. EV was making an effort to break into the broadcast market that was pretty well dominated by RCA and Western-Electric up to this time.

EV engineers had developed some innovations in mike technology like utilizing the smaller more powerful magnet material developed during WWII. Also EV had developed a new type of microphone diaphragm they called Acoustalloy. This new mylar-plastic material produced a smoother, wider frequency response than the metallic diaphragms used by other microphone manufacturers. [See the PDF file for more details.] These two developments gave Electro-Voice an edge in breaking the monopolies enjoyed by RCA and Western Electric.

Many radio station and network engineers were slow to change from the old “standbys” of the industry. As an aside, Western Electric had gone out of the broadcast equipment business by 1950 and their microphones were now manufactured by Altec-Lansing but still maintained popularity with radio and TV audio engineers.

These two high quality dynamic microphones had high output as well as extended smooth frequency range that made them naturals for many uses in broadcasting and recording.

The 645 and 650 mikes did not gain huge popularity but were used by some stations and networks. The two mikes did pave the way for the introduction, in 1950, of the new Electro-Voice “Slim-Trim” line of one inch diameter “stick mikes” that did enjoy great acceptance by the broadcast industry.

Thanks for dropping by the Modesto Radio Museum site.