Crash Course on Microphones and Polar Patterns

Does every microphone look the same to you? Does trying to choose which microphone to use make your head hurt? In this post, I'll give you a crash course in microphones and polar patterns. Unfortunately, this part of the job is never really talked about in music teacher school. Don't worry, though, I'm here to help.

Microphones and Polar Patterns

First off, what is a polar pattern anyway? Polar patterns are, essentially, how the microphone picks up sound. There are many varieties of polar patterns, the most common for a vocal microphone being cardioid (upside-down heart shape). Please check out this visual to get you started on polar patterns.

Understanding microphone polar patterns. Graphic originally published in Technology for Unleashing Creativity from Oxford University Press.

What Microphones are Best?

I often get the question, "Well, what microphones do I need?" and to that question, I always respond with, "Well, it depends on what you want to do." For example, if you are only doing solo singing and/or public address, a dynamic vocal microphone like the Shure SM58 or Beta 58A will be all you need. But if your program, classes, or performances require more than that (which it often does in our line of work) there are a few other considerations you need to make.

Dynamic vs. Condenser

Typically, condenser mics are for picking up large groups (like choirs) or something far away, but are also used for close-range recording because of their sensitivity. Dynamic mics are often (but not always) designed to be handheld and for picking up sounds that are relatively close, like with solo vocals or an instrument. Condenser mics also need a boost of energy called 48v Phantom Power which is activated by a small button located on any sound board. You cannot just plug in a condenser mic into a speaker and expect it to work, but you can do that with a dynamic mic making dynamic mics a little more versatile in some situations. A common dynamic mic for vocals is the Shure SM58 (discussed earlier) while a common wide diaphragm condenser (known for their warm output) is the AudioTechnica AT2020 often used for vocals or for podcasts. Small condensers like the Rode NT5 are common small diaphragm microphones often used in some instrumental settings.

Microphones and polar patterns 101.

Choirs and Vocals

For choirs, it would be common to use cardioid condenser microphones like the AT2020 for the group; three to four up front, depending on its size, and a dynamic vocal mic like the SM58 or Beta 58A for any solo singing.

Jazz Bands

Jazz bands often don't need a whole lot of micing or amplification aside from the guitars and bass. A solo mic or two for each section so the solos can cut through the band would be a minimum in some settings. These microphones can be vocal or instrument microphones. Instrument microphones are often exactly the same as a vocal microphone but with a different grill on the top. Instrument microphones like the Shure SM57 are common.

Minimum setup for micing a jazz ensemble.

Rock/Popular Music Ensembles

If you are running a rock or popular music ensemble, you will need a number of different microphones for various applications. This would be one of the most extensive setups you may come across. Also, you could get by with just the vocal mics for the singers and horns, and rely on the amplifiers for the keys, bass, and guitar, but that will depend on the venue. I find, that in many settings, drums do not need to be mic'd. At very minimum, if you plan to mic the drums, it would be two overhead small diaphragm condenser mics like the Rode NT5 and a kick drum mic like the Shure Beta 52A. Guitar amps are typically mic'd with an instrument mic while the others are DI'd into the board. DI stands for Direct Injection and they allow an instrument that uses a patch cable (1/4 inch) to be turned into a mic cable (XLR) signal that can be plugged into the board. More on sound boards and DI's in this post.

Minimum setup for a rock ensemble/popular music ensemble

Recording and Extras

If you are using Digital Audio Workstations like Soundtrap or BandLab, having a collection of condenser mics with audio interfaces and studio headphones would be useful. These can be used for podcasting, recording vocals, and for recording instruments. Condenser microphones are typically used in recording contexts because of their sensitivity and quality of sound.

To Review

Choir and Vocals

• Enough condenser microphones for the group.

  • AT2020, Rode NT5, Apex 415B.

• Solo singing.

  • Shure SM58, Shure Beta 58A.

Jazz Band

• Enough vocal or instrument mics for instrument solos or vocal solo.

  • Vocal: Shure SM58, Shure Beta 58A.

  • Instrument: Shure SM57, Shure Beta 57.

Rock/Popular Music Ensemble

• Enough vocal mics for vocalists.

  • Shure SM58, Shure Beta 58A.

• Instrument mics for guitar amps and/or horn sections.

  • Shure SM57, Shure Beta 57.

• Drum kit micing.

  • Rode NT5 for overhead (You can get by with one per drum kit).

  • Shure Beta 52A Kick Drum mic.

Recording

• Condenser microphones with USB audio interfaces.

  • AT2020, Rode NT5, Apex 415B.

• Audio Interfaces (for plugging mics into a computer).

  • Focusrite Scarlett 2i2, Behringer UM2.