[Elecraft] Signal analysis with the P3

[Jim Brown]

On 4/29/2014 9:32 AM, Fred Jensen wrote:
> As I got closer, I became more and more a bass.  Our "anchorman" was 
> right up on top of the mic sitting on his desk. 

That characteristic of a mic is called "proximity effect," and is the 
result of the combining of front and rear openings to a mic capsule to 
form a directional pattern. Most such mics have a cardioid pattern,named 
because it is sort of heart-shaped. Most hand held mics intended for 
live performance are cardioids, and have this characteristic.

In the 1950s, the engineers at Electro-Voice invented a cardioid mic 
with an additional opening farther down the handle of the mic that 
greatly reduced proximity effect. That mic, the model 666, came to be 
known as the "Buchannon Hammer," because it was demonstrated to 
broadcasters by using it to drive a nail to prove its ruggedness. EV 
still makes excellent mics using this principle, and they are quite 
popular in broadcast. One of them, the RE20, is the one you see most 
often on TV on a boom with a talk radio jock. The mics I use for NCCC 
meetings are RE16s, a smaller, handheld version that uses the same 
principle.

Over the years, omnidirectional mics have also been popular with 
broadcasters, because they have no proximity effect. EV pretty much owns 
that market too, their model 635A having been a standard for at least 40 
years.

And it was one of the two founders of EV, Al Kahn, K4FW, who founded and 
ran Ten Tec when his partner decided they should sell the biz to a 
conglomerate. Al was a CW guy. I worked him once.

73, Jim K9YC