Understanding Microphone Polar Patterns for Recording

 

Hi everyone!

Over the past few weeks many of you have sent me your music to listen to. I have been listening and speaking to you individually about your mixes and the way you recorded them. The main thing that I picked up is the use of microphones in the recordings, the way they are placed and specifically what microphone used and the polar pattern of them.  

When people approach me to listen to their music, the first thing I ask is what microphone, equipment that they have used. This then gives me the understanding of what to expect when the sound is recorded at source. I love listening to raw recordings before a mix has been done so I can hear any imperfections before any chance of manipulation.

I wanted to do a post specifically about microphones and the uses of their polar patterns so you can all familiarise yourself with them during your recordings. I hope you find this helpful and refer back to anything here that I have said when you are creating your records. Please enjoy!

Knowing the difference between polar patterns will help you achieve better recordings. The main reason for writing this is to highlight the benefits of different patterns and what they have to offer when recording anything in the studio. I will not go into depth about stereo micing purely because I want you to understand single microphone applications, this way you’re not loaded up and have simple basics down.

There are six main polar patterns; omnidirectional, cardioid, supercardioid, hypercardioid, ultra directional and figure of 8. Each will provide you with a different recording perspective, but I will only focus on the main ones you will find when being in the studio or live sound. This way you will understand the most important and familiarise yourself with patterns that you come into contact with in your recordings.

The most popular pattern that you will see is cardioid. A cardioid microphone is your ‘Jack of all trades’ mic because it can be used on stage as well as in the studio. When a sound wave hits a cardioid microphone the pick up of sound should be directed at the front of the mic because that is where it is most sensitive. This is key for recording instruments in an isolated environment like the studio. If you’re recording a guitar or a drum kit, you really don’t want the sound to bleed through, so having the polar pattern of a cardioid will help you pick up a more precise sound that is forward functional to the source aiming at it.

If you’re recording your drums and guitar together you don’t want the mix to be muddy and have each sound filter through each microphone you use, so close mic your guitar cab for a clearer sound, just like every part of your kit. You will also find this easier when you’re mixing.

Live sound performances are the same when it comes to cardioid mics. Next time you’re at a gig, look out for microphones being used. Vocalists will use a cardioid microphone because it will focus directly to the voice and pick it up clearly. It keeps unwanted sound out of the mic from the other instruments around the vocalist as well, this way it minimises the risk of feedback from the amps and PA.

Omnidirectional microphone patterns pick up sound in a 360-degree radius, so all sound is sensitive around it. This pattern is perfect for studio recordings because it picks up a natural true sound. Acoustic recordings are ideal for this pattern if you want that full room sound. Live sound performances are not for the faint hearted, especially for an omni, so they are best left in the studio or a home recording for live performances that feature you and your guitar.  This pattern can pick up a wide sound source so you can use this kind of microphone for a piano in an acoustic recording. You’re not limited with creativity acoustically with this pattern.

It is ideal to not use an omni microphone in an untreated room because you will pick up the room ambiance on the recording. If you have a buzz or a hum in the background of a raw recording it is harder to remove it than you think, so please take room acoustics into consideration before you record with this pattern. If you do not have an acoustically treated room and want to record professionally, please stick with micing up your equipment and vocals with a cardioid so you can enhance your recording quality.

Supercardioid is what it says on the tin but with a few added extras. The pickup on this pattern is narrower and has a greater rejection of sound; they also pick up sound from the rear end of the microphone. Live sound or studio, these microphones are best suited for single sound sources that need to be picked up; woodwind, brass, drums etc. are ideal for being recorded with this pattern.

Because this microphone pattern picks up sound from behind the microphone it is advisable to not place your monitors in front of it when you are performing. If you still need your monitors and are performing, position your monitors about 120-degree off-axis to avoid feedback and aim them away from the mic to avoid any bleed into the microphone.

Figure of eight is all in the name really. The shape of the polar pattern is in a 8 around the microphone and where the 8 pattern is that is where the sound is sensitive. In the sides is where sound is rejected from source; this is where you focus on what you will use this kind of microphone for.

In live sound you wouldn’t use this pattern because of the sensitivity range but depending on whom you work with or what kind of experimentation you’re after, as long as the environment is VERY controlled you can record a group or a duo for a natural sound. It isn’t advisable but I’m all game for experimentation in music just to test limits of equipment and creativity.

In the studio is the perfect fit for this pattern. Duets, vocal or instrumental allow you to record freely and create that stereo imaging with a natural acoustic sound. Vocals are not the only thing you can use this for, I have often used this pattern for overhead recordings on drums to get that spread in sound because they capture a wide range. However, that’s down to you and your personal choice.

Another key thing worth remembering is that polar patterns maybe printed as diagrams in two dimensions, the real pattern is three-dimensional. So make sure you are aware of that. Also, in the specifications of some microphones they will offer you a switchable polar pattern. These are only two fundamental polar patterns, figure of eight and omnidirectional. Please do not be fooled into thinking these patterns can be changed from one to the other on a dramatic scale.

Choosing a condenser microphone or a dynamic is vital, but so is the polar pattern accompanying it. Please make sure you research your purchases and what the microphone you are intending to buy is suitable for recording. 

There are always audiophile’s out there to help and encourage you with advice! Please find us, we do exist!

Happy recording!