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Audio-Technica AT2020USB Cardioid Condenser Microphone
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DPA d:dicate 4018F Supercardiod Microphone
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CAD Audio A77 Side Address Dynamic Vocal Microphone
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Shure MV51 Digital Large-Diaphragm Condenser Microphone
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AKG EC82 MD Microlite Series Condenser Microphone
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Countryman A3 Podium Microphone
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Point Source CO-8WD Series8 Headset Condenser Microphone
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Sennheiser MKE 2 Digital Condenser Microphone
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Audix HT7 Condenser Headworn Microphone
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Blue Microphone Bottle Rocket Stage One Solid State Microphone
Hearing and understanding voices—words both spoken and sung—is arguably the most critical audio element of a worship service. The congregation embraces the meaning of sermons, prayers, and hymns through those words and how they are presented. Since all but the smallest worship groups use a sound system to communicate much of the service, it must clearly and intelligibly project the voice to listening ears.
The audio signal chain begins with microphones. Their quality, audio characteristics, and how they are applied to voices (and instruments) will have perhaps the most important effect on what your congregation hears. In this article, we'll look at different microphone technologies, coverage patterns, and response characteristics—and how these can be applied to particular vocal reinforcement applications and types of voices. We'll also look at some methods for testing and choosing microphones.
CONVERTING SOUND
The basic microphone technologies are dynamic and condenser—the means by which the sound waves from the voice or instrument are converted into electrical impulses to be processed and amplified by the rest of the audio system. Dynamic mics move a coil of wire—attached to a thin membrane—within a magnetic field to create a current that is analogous to the sound source. Ribbon mics use a thin metallic “ribbon” suspended in a magnetic field, so also function on a similar principle. Condensers have a thin diaphragm separated by a small air gap from an electrically charged backplate, and as the sound waves move the diaphragm closer to and farther from the backplate, the varied capacitance creates an electrical equivalent to the original sound.
DYNAMICS
Dynamic mics are traditionally the workhorses of the audio world. Since the sound waves need to move a more robust diaphragm with a voice coil connected, dynamics have a greater moving mass than a condenser or ribbon. Dynamics are typically rugged, handle high sound pressure levels (SPL), are somewhat less responsive in the very high frequencies, moderate in sensitivity, and priced in the lower to mid range—though a neodymium magnetic structure adds several dB to the output compared with a conventional magnet, and other innovations have improved their high-end frequency response.
They do not require phantom power, don't typically have as fast and accurate of an impulse response as other mic technologies (which can sometimes be beneficial for smoothing out harsher elements from a sound source), and are available in patterns from omni to hypercardioid. Dynamics can be great for vocals and spoken word, and many of the better recent offerings have an excellent, balanced frequency response over a wide range, and articulate high frequencies. These mics tend to give warmth and reinforcement to the fundamentals of the vocals, and can add fullness to a thinner voice—especially when used close to the mic to take advantage of the bass boost from proximity effect.
Ribbon microphones designed for live vocal applications are rare, but can be used effectively for voice in a more controlled recording environment. Ribbons are usually a side-fire design, and capture audio from the front and rear in a figure-eight pattern. Traditionally the most delicate microphone design, modern ribbons from several manufacturers are robust enough for live use, where they are used mainly for acoustic stringed and wind instruments and guitar amps. As audio instruments, their transient response is more accurate than a typical dynamic due to the lesser mass of the ribbon, with a smooth frequency response that is often somewhat warmer and less crisp on the high end than a condenser. I know of only one microphone that uses ribbon technology in a handheld format designed for live vocal applications—the beyerdynamic TG V90r.
CONDENSER MICROPHONES
"Dynamic mics are the workhorses of the audio world. Since the sound waves need to move a more robust diaphragm with a voice coil connected, dynamics have a greater moving mass than a condenser or ribbon mic."
Gary Parks
The mass of the moving diaphragm is less in a condenser than a dynamic, making it more sensitive to the tiny variations in air pressure, and thus yielding better transient response and more extended high-frequency response. Some condensers have smaller diaphragms—such as pencil condensers, many handheld condensers, and miniature instrument and headset mics—and others such as studio-style side-fire mics feature larger diaphragms. In general, smaller diaphragms provide a wider frequency and dynamic range, and the ability to handle higher SPL, but offer a bit lower sensitivity and higher self-noise (though still very quiet for live use) than the larger ones. Condensers require external power to function, usually via the mixing console's phantom power or sometimes with an internal battery.
A quality handheld condenser in the hands of a good vocalist can sound great, offering a quite accurate reproduction of the vocalization, including the sibilance, breathiness, and dynamics of their delivery. The excellent transient response of these mics can give the vocal a recording studio quality through a good audio system. In recent conversations with several engineers, the newer condensers are cited as their favorite vocal mics, giving a natural sound with almost no additional EQ, an “airy” high end, and consistent off-axis frequency response.
The sound of a condenser in the higher frequencies is often characterized as crisp and sometimes bright, though in some cases and with some voices (and instruments) they reproduce these higher frequencies so distinctly that the result can turn edgy or brash—so they're not the universal solution. Condenser mics are frequently used for acoustic instruments, such as guitar, mandolin, violin and other bowed strings (with the miniature versions mounted on the instrument), and also with reed instruments and flutes.
HEADSET MICS
Headset mics featuring miniature condensers on a boom have become a standard for pastors as well as singers who move a lot or must be hands-free to play an instrument. To promote freedom of movement, they are usually connected to a wireless beltpack. Headsets are by far the best choice for these types of applications.
As with all microphones, considerable differences in quality and performance can be found. Opt for a professional headset that offers a full, smooth frequency response, excellent articulation, and a higher resistance to feedback. Several manufacturers specialize in miniature condenser microphones, and this is a good place to start.
Headset mic advantages include very good gain before feedback, a more natural voice quality with full frequency response (especially when compared with lavalier mics), and consistent audio level with movement. Placing the mic element toward the corner of the mouth but out of the direct line of the voice minimizes breath noise and consonant pops, when used in conjunction with the provided windscreen. Omni headsets work well at these close distances, while directional headsets can provide additional isolation when more than one headset user is talking in close proximity with others.
COVERAGE PATTERNS
For live applications, directional microphones are used almost exclusively (with the exception of headsets with omni elements that are used right at the mouth). The cardioid pattern presents fairly wide and even coverage in front of the mic, attenuating gradually at the sides to around 90% off-axis, and much more rapidly toward the rear, with the greatest attenuation at 180% from the front. A singer can approach a good cardioid mic from directly in front up to a relatively wide angle and still maintain fairly consistent frequency response with little attenuation in level.
Variations on cardioid polar patterns include supercardioid and hypercardioid. Tighter polar patterns mean that the microphone attenuates more of the sounds coming from the sides—therefore potentially providing more isolation, but also mean that the vocalist must be more careful to sing into the front of the mic to avoid introducing too much attenuation and frequency response coloration to the resulting sound. The supercardioid pattern is fairly commonly used, attenuating more rapidly toward the sides than a cardioid and with a narrow lobe of increased sensitivity directly at the rear.
A hypercardioid mic is even more directional and better at isolating a single voice, and also has a larger pickup lobe at the rear, with its greatest attenuation about 35%- 45% from the back of the mic. The tighter patterns are better used when one vocalist is using a mic, rather than when a mic is shared by two or more singers approaching it from off-axis. Also, position any monitor wedges accordingly to correspond with the greatest null in the mic's coverage pattern.
TESTING OUT A MIC
When checking out a new microphone for vocals, use some of these “tests” to see how it performs. Sing and talk into it directly in front and then move to the sides; hear how it sounds on-axis and whether the sound is consistent when someone sings into it at an angle, and how far off-axis it can be used. Sing or talk into the rear of the mic and notice how well it rejects audio there, and whether it attenuates across all frequencies or just in the higher frequencies and is still quite noticeable in the lower pitches of the voice. Sing into the mic from two or three inches away and hear if it still sounds full and has decent level, and then move in close to check the amount of bass boost from proximity effect.
Sing or speak quite loudly to test how well the mic can handle higher SPL sounds without distorting or overloading. Use some S-sounds and lip-smacking noises to check out the high frequency and transient response. And from on-axis and moderately close, make sounds with the letter “P” and some other more breathy consonants to see how well it handles plosives without making popping sounds, and how sensitive it is to breath and wind sounds. Tap and rub your fingers on the mic handle to hear how well damped those noises are. You'll learn a good bit about the microphone and its capabilities by trying some of these techniques, and which mics might be good choices for particular singers based on their voices and how they approach a microphone.
You may have noticed how different people can sing the same note, and one voice sounds richer or deeper or louder while another is thinner or more nasal or breathier and quieter. Some may enunciate more than others, or even overly push consonants so that the mic pops. This tonality and balance of fundamentals and overtones can be shaped by the choice of microphones—dynamic or condenser, a more modest or enhanced high-frequency response, a flatter or more shaped overall frequency response curve, having a low-end rolloff switch (or rolling off some of the lowest frequencies at the console), the amount of proximity effect, and so on. There are many variables in both voice and microphone, so try out voices on a few mics if you have the opportunity.
MAKING A CHOICE
The microphones you choose for particular vocalists will depend on what you already have on hand, your budget, the requirements and overall quality of your sound reinforcement system, the size and characteristics of your worship space, and the voices and skills of the singers and presenters. Either using a $600 handheld condenser with a lower-end powered mixer/speaker combo or a $30 cardioid dynamic with a professional audio system is not the wisest use of resources. However, since the microphone is what initially “hears” the voice, and the rest of the signal chain only processes and amplifies that audio signal; taking some time to try some options and then selecting a higher quality microphone is the best bet.
