What You Don't Want The Mic To Hear

So much of a great recording boils down to where you choose to place the mics. Microphones don’t have brains so you need to point them and place them in the best position to “hear” what you need them to “hear.” But just as important as what good sounds are coming into the microphone is avoiding bad sounds from getting into your microphone as well. Let’s discuss.

Via Will Fisher Flickr

Use The Back Of Your Microphone

In most recording situations, you’ll tend to use microphones with a cardioid polar pattern. This means the microphone primarily records what is hitting the front of it while simultaneously rejecting most of the sound that hits the back of it. Pretty straightforward.

But if you think about that for a second, that the mic will reject most of what hits its back, you can see the potential you have for making better recordings. Not only should you point that mic at what you WANT the mic to hear (your voice, acoustic guitar, snare drum, etc) you should point the back of the mic at whatever you DON’T want the  mic to hear. Examples of unwanted noise could be a computer fan, outside window, air vent, or other musicians/instruments recording at the same time.
 

The Two Headed Monster Of Mic Placement

This type of thinking makes your mic placement strategy twofold: you first think about where you want the mic facing so as to pick up the best sound of the given instrument. This could be mean putting the condenser mic a foot away from the acoustic guitar’s sound hole, facing in to the 12th fret.

Secondly you then decide to have the back of the mic facing your bedroom door to minimize the sound of your roommates watching football down the hall. This second move determines where you sit while recording the guitar. Your first decision was regarding mic to instrument, while your second decision was regarding mic/instrument to outside noise. Got it?

Improve Your Live Mic Setup

This type of “back of the microphone” thinking is critical to good live sound, even if you don’t plan on recording the show. So much of mic placement on a stage is about rejecting other sounds and getting as much isolation as possible given the noisy environment.

On a live stage you don’t have the luxury of recording every instrument separate, so you are constantly thinking about what the mics are hearing and not hearing. You balance the two in and almost endless state of compromise, looking for the best placement. If you think like this though, your live sound quality will dramatically improve as you minimize bleed and potential feedback. Awesome.