The 664 sold for $51.00 in 1962 and the optional EV-419 base (shown) was available for $6.00. Dual output impedances of 150 Ohms or Hi-Z and an output of -55db. The directional characteristics of 50% exclusion of side noises and 90% exclusion of rear noises allowed for large distances from the microphone to the source without stray pickup. It looks most like the one from the mid 50s except no serial number. It has 'Conneaut Ohio made in USA' all one one line under the Astatic logo. The cavities provided the necessary amplitude and phase conditions to result in a pattern that was constant over a wide frequency range. There is no serial number, where most of these have the serial number, mine says 'CERAMIC'. Utilizing what EV called 'Variable D', which was comprised of three sound canceling entrances into cavities at different fixed distances behind the diaphragm providing a front to back spacing that varied in distance (from the diaphragm) inversely with the frequency, the 664 demonstrated a highly directional cardioid pattern. Electro-Voice Cardioid Directional Dynamic Microphone Type 664 The EV-664 was primarily a communications microphone with highly directional characteristics. Click to expand.The Astatic D-104 was made from 1930s to 2000 - a true 20th century microphone. Eminem The Marshall Mathers Lp Zip 2000 Sp more. While the V-2 ribbon mikes may have been used in some of the smaller BC stations, it's more likely that they were mainly for PA applications. Or serial number thats assigned to each new object instance: An Invoice class might maintain a static field that holds the invoice number that is assigned to the.

Astatic serial numbers