diy shotgun microphone interference tube.

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I notice all the directional mics stop the perferations some distance from the mic capsule, is this an important dimension?
 
i think the interference tube turns cardiod to omni untill the holes or slots are added the holes make shotgun mic super or hyper cardiod .
 
I'm disappointed in the non labeling of the attenuation on beamwidth charts, Oh, they label degrees on them, which I don't need, but no label on the db lines or whether they are even in reference to db. One could assume they are 3 db, but the only chart I gave seen lately that had a label, was 5db per line. Arrgh!
Traditionally, the ticks are 5dB. However, there are exceptions, typically from dishonest sources.
 
Last edited:
i think the interference tube turns cardiod to omni untill the holes or slots are added the holes make shotgun mic super or hyper cardiod .
If you wanted the interference tube to work down to 50 Hz, it would need to be 1.7m long (almost 6 ft).
In order to keep dimensions acceptable, the pattern shifts from interference-controlled to delay-controlled cardioid.
At high frequencies; where the capsule size becomes comparable to the wavelength, the interference tube ceases to operate, leaving place for diffraction controlled directivity and masking of the rear-axis waves by the closed back of the mic.
 
If you wanted the interference tube to work down to 50 Hz, it would need to be 1.7m long (almost 6 ft).
In order to keep dimensions acceptable, the pattern shifts from interference-controlled to delay-controlled cardioid.
At high frequencies; where the capsule size becomes comparable to the wavelength, the interference tube ceases to operate, leaving place for diffraction controlled directivity and masking of the rear-axis waves by the closed back of the mic.
so about 5.5 feet , 5.57743 , though would it work. if used for outdoors.
 
would hypercardiod be easier like my c451s use that outside.
just eq, anyway i will probably and record diologue voiceover with a ribbon. as everyone is wearing covid masks fix in post is much easier and the the one of the pm2 mics indoors. , is it easy to match a 451 to a ribbon with eq. i would think the 451 sounds kind of ribbony through bit bright.
 
Last edited:
are these good references.
 

Attachments

  • 51CYGdUKeYL._AC_SL1500_.jpg
    51CYGdUKeYL._AC_SL1500_.jpg
    21.7 KB · Views: 11
  • 61BcNzG2xEL._AC_SL1500_.jpg
    61BcNzG2xEL._AC_SL1500_.jpg
    63.4 KB · Views: 12
I'm no machinist, but there are machinist forums just like there are electronics forums. I think you would find better answers there for this kind of problem. I think you will be dissatisfied with the results you can get from a drill press.
 
Back
Top