Short/Medium/Long Shotguns - What's the Diff?
 

Do the terms "Short," "Medium," and "Long" in the names of shotgun microphones refer to anything except their physical dimensions? For example, in the Sennheiser line the K6/ME66 is referred to as a "short shotgun" while the ME67 is a "long shotgun." All other things being equal, what might we infer about the acoustic differences between the 3 different mic types? And of course, I realize things aren't that simple in the real world and you need to compare apples to apples- for instance, the ME66 is a short shotgun but so is the MKH416 according to Sennheiser and I think the experts would say they have quite different characteristics (and they also have quite different prices!) So what's it all mean, Daddy?

As I understand, the longer the mic, the longer the interferrence tube. The interferrence tube is an acoustic resistor whose resistance increases as the sound source (or wave front) moves off the central axis. The longer the interference tube, the tighter the mic's pattern. The acoustic resistor characteristic vaires across frequency. I suspect the money goes to improving the mics performance across frequecies, especially lower frequencies, and the problem of the back-lobe pattern, where the acoustic wave comes from directly behind the microphone. In that case, the interferrence tubes doesn't block the sound very well, especially in cheaper shotguns.

I think of it like a real shotgun.
The longer the barrel, the more accurate and condensed the buck shot comming out. A sawed off shotgun hits a huge area, but not too accurate. A hunting shotgun has a looooong barrel and is pin point (as close as a shotgun can be) accurate, not hitting anything around the target.