I have frequently heard the advice: “You should not use Shotgun microphones indoors, and should instead use Small Diaphragm Condensers”, but I had never put the idea to the test, so I wanted to provide those sound tests so you can hear the potential issues that may arise from using a shotgun mic indoors.

1. Does a Shotgun Microphone reject more reverb?

   • I can’t say 100% the time yes because it depends on placement of the mic in relation to reflective surfaces. But I noticed that in a decent positioning near a desk and computer monitor, it DID pick up slightly less reverb compared to a cardioid small diaphragm condenser.

2. Does it reach out and grab the reflections off of surfaces?

   • No. Not in my test. When I pointed both mics directly at the desk and spoke towards the desk, I heard no significant difference in the amount of reflections picked up off the desk. The shotgun mic did sound tonally much worse though.

3. Does off axis coloration of shotgun mics ruin your recording?

   • Sort of, yeah. The off axis coloration of shotgun microphones is horrible compared to the cardioid small diaphragm condenser that I compared it to. When I went off axis on the Shotgun mic, we lost all the detail and top end information and it sounded dull and lifeless. The SDC was much more forgiving as you moved off axis where it did not exhibit that same loss of high frequency information.

4. Does speaking off axis cause phasing issues on a shotgun mic?

   • Kind of! I was surprised to find that it can encounter some phasing issues where you get some comb-filtering type artifacts and some sounds sounding like they’re cancelled out and hollow. My very basic understanding of this is due to the voice entering the different slots of the interference tube causing that phase cancellation.

5. Do shotgun mics exhibit phase issues due the reflections.

   • They can. When I tested the SDC and Shotgun directly next to my desk, my voice bouncing around the room did start to impact the shotgun a lot more than the SDC. I started to notice some of those phase artifacts and comb filtering. Admittedly both mics sounded AWFUL in this situation, but I didn’t notice the same issues on the SDC.

CONCLUSION

Now that I understand and have heard the issues used to justify the advice “use an SDC indoors instead of a shotgun mic” I partially agree with the advice. If you’re constantly moving your shotgun mic around to follow talent and you may end up with your mic near walls or desks or other surfaces that reflect sound waves around, I completely agree with the advice. However, if you have a static microphone setup, if you have a decently treated room, and you don’t have the mic next to reflective surfaces, I think that a shotgun microphone could still offer some benefit in reverb rejection compared to the SDC.

When it comes down to it your room and the mic placement is one of the biggest factors in how good the recording will sound. If you have some treatment in your room, can overhead boom, and get the mic closer to your mouth 12-inches or so, you should be able to get great sound with an SDC or a Shotgun mic. If you have an SDC mic, use it. If you have a shotgun mic, use it. In both situations you’ll just need to be careful about mic technique and mic placement, just more so with the shotgun mic. .

Clip from BSP-403: https://www.youtube.com/watch?v=G-60QAwupyA
Originally aired: 29 SEP 2024