Shotgun microphones...

[wheelema]

... are not advised for use indoors. And that's fine, but I need some clarification on something.

I understand that a shotgun mic does not handle sound reflection well... which is why they are usually not suitable indoors. But the interference tube (which works so well outdoors and so poorly indoors) receives sound from the sides, while the sound you WANT to capture is captured directionally from the front.

But if you could cut that interference functionality out of the circuit, wouldn't you have a plain old (albeit longer) super cardioid/hyper cardioid mic?

 

[ittam]

"An Interference Tube is simply a long metal tube with a series of circumferential slots cut into it, fitted onto a directional Microphone. These slots produce interference patterns in sound waves from the sides, resulting in partial cancellation of off-axis sounds and a resultant apparent increase in the gain of sounds from directly in front. "

Think of a mic of this type as a cardioid or hyperc. mic with the interference tube in front adding directionality to wavelengths shorter than the tube

You could cut the front away from the mic but then it would not be a long one anymore... ( please don't )

The rear lobe is not so big ( hypercardioid has one also ) and there are ones without it ( Sanken ).

Matti

 

[wheelema]

Thank you.

 

[ittam]

You are right about the interference tube getting kind of confused in
small to medium indoor spaces and hypercardioid or even cardioid mics
are often used instead for film / tv dialogue

Matti

 

[wheelema]

You are right about the interference tube getting kind of confused in
small to medium indoor spaces and hypercardioid or even cardioid mics
are often used instead for film / tv dialogue

Matti

What I don't understand... unless it's simply an example of money-money-money... why a manufacturer (who after all manufacture different capsules for common mic bodies) manufactures a mic that converts from a super/hyper cardioid shotgun (with interference tube) to a 'regular' super/hyper cardioid.

Unless I'm missing something it seems to be the most straightforward of propositions.

 

[ittam]

I thought that I just answered that...
As I wrote the interference tube has higher directivity towards higher
frequencies being an acoustical component, think of wavelenghts of sound.
A cardioid or hyper is much more uniform in its responce, esp. off axis.

Matti

 

[wheelema]

I thought that I just answered that...
As I wrote the interference tube has higher directivity towards higher
frequencies being an acoustical component, think of wavelenghts of sound.
A cardioid or hyper is much more uniform in its responce, esp. off axis.

Matti

I appreciate the clarification.