The Electro-Voice 655C Slim Trim dynamic omnidirectional microphone
Description and Applications The Electro-Voice Model 655C microphone is a dynamic, omnidirectional type designed for highest quality FM, AM, and TV broadcasting. The traditional concept of bulk in broadcast microphones has been abandoned in the Model 655C. Its slim design is made possible without the necessity for closely associated auxiliary equipment. Wide frequency response, wide pickup angle, and light weight make it ideal for many BC and TV applications where size is a factor. It is equipped with an integral Electro-Voice Acoustifoam filter which minimizes wind and breath blasts.
The Model 655C can be mounted on a stand coupler which permits tilting the microphone through a 90-degree arc. It can be mounted also on a floor or desk stand, on a boom, or carried in the hand.
This high-quality microphone features the exclusive Electro-Voice Acoustalloy diaphragm, which permits smooth response over a wide frequency range and withstands high humidity, temperature extremes, corrosive effects of salt air, and severe mechanical shocks. It is practically indestructible with normal use.
Figure 1
Specifications
Type: Dynamic
Frequency Response: Uniform from 40 to 20,000 cps. See Figure 1
Impedance: 50, 150, and 250 ohms (connected for 150 ohms when shipped). See Figure 4 for instructions for changing impedance
Output: 50-ohm impedance: -57 dB; EIA sensitivity rating, -150 dB 150-ohm impedance: -57 dB; EIA sensitivity rating, -151 dB 250-ohm impedance: -57 dB; EIA sensitivity rating, -149 dB 0 dB = 1 mw/10 dynes/square centimeter
Polar Pattern: Essentially omnidirectional, becoming directional with rise in frequency. See Figure 3
Diaphragm: Electro-Voice Acoustalloy
Magnetic Circuit: Employs Alnico V and Armco magnetic iron in a nonwelded circuit
Case: High Tensile, lathe-turned aluminum
Finish: Nonreflecting gray
Net Weight: 7 ounces, without cable
Cable: 20-foot, three-conductor, shielded, neoprene-jacketed, broadcast type; equipped with Cannon UA-3-11 connector which mates with UA-3-12
Stand Coupler: ⅝"-27 and ½" pipe thread provided on microphone stand connector
Standard Accessories: Carrying bag, Model 300 clamp
Figure 2
Figure 3
Figure 4
Figure 5
Text and illustrations are from the Electro-Voice Engineering Data sheet, Part No. 530981
The Electro-Voice 655C Slim Trim omnidirectional dynamic microphone.
From time to time Electro-Voice would publish Microphone Facts for the operating engineer, a series of newsletter-styled three-ring binder-punched bulletins that described new products. Here is an example from November, 1958, which discusses a specific single-mic application of the Model 655C. It is four pages in length, and is formatted for high-resolution printing on 8½ by 11-inch paper. It is a 1.8-megabyte PDF.