For the most part, microphones can be classified by how they convert sound energy to an electrical signal. The most common types are condenser and dynamic. In a place of worship, condenser microphones offer a number of advantages over dynamics. First, condenser microphones can be made much smaller (and less conspicuous) than dynamics without sacrificing performance. They also have higher sensitivity for excellent pickup, even at the distances required by hanging choir mics. They have lower handling noise than dynamics, and their extended frequency response provides a crisper, more accurate reproduction of sound. Finally, condenser mics have superior "transient response" for accurately reproducing sudden sonic impulses, such as those produced by voice, piano and percussion. Condenser microphones require a power source for their internal electronics. Some models can receive power from an internal battery while others may be "phantom" or "remote" powered.
Microphones are also classified according to the way they pick up sounds from different directions. An omnidirectional (omni) mic picks up sound equally well from all around. A unidirectional (uni) mic picks up mainly what is directly in front of it. The most common type of unidirectional mic is the cardioid type. It has a broad angle of pickup in the front, and rejects sounds from behind the mic. Supercardioid is a tighter pattern, but with more pickup from the rear than cardioid. Hypercardioid is tighter still, with even more pickup from the rear. Because they reject feedback, room reverb and leakage, unidirectional mics are the most common choice for sound reinforcement.
Both VHF and UHF frequency bands are shared with a large number of other devices including TV stations, communications equipment and a large number of wireless microphone systems. Because of this sharing there is the possibility that someone else (anotherchurch) in the area may be using the same frequency. You should not use two microphones with the same frequency. This will result in interference and render the system useless. Manufacturers often sell a wireless handheld and lavaliere or instrument microphone package. Although these systems are designed for individual users, they are not intended to be used simultaneously. Each mic can be used with the same receiver, however they cannot operate at the same time.
Wireless microphones are usually sold with one or two antennas. Dual antenna or “diversity” systems are able to avoid dropouts because they have two antennas and two receiver channels. Because the chances that there will be simultaneous dropouts at both antennas are extremely low, diversity receivers provide almost complete immunity from dropouts. Diversity wireless systems will almost always have better operating range than similar non-diversity systems.
For stage vocals use a dynamic handheld cardioid mic, such as the Shure SM-58. Every church should have an adequate stock of this workhorse microphone, as they can be used in place of most microphones when failures occur or when you have expanded needs. If budgets allow, try using a condenser cardioid like the Shure SM-87. Higher quality microphones will always produce better results in your mix and on stage.
When micing a piano try using a stereo pair of cardioid mics (preferably condenser, like the Sennheiser ME-40) aimed inside the piano at half-stick or full-stick open. If your church has an upright piano, open the top lid and aim two condensers in, or, alternatively, point two condensers at the back sounding board of the piano. If your worship team uses a keyboard, invest in a high quality direct box to convert the signal from unbalanced ¼” to balanced XLR inputs and run directly into the console.
There are a number of high qualities microphone “kits” specifically designed for micing drums and percussion. If you don’t have the resources to buy a complete drum mic “kit”, you should at least invest in a dynamic mica such as the AKG D112 for use on the kick drum. You can easily substitute a Shure SM-57 on the snare and employ two condensers or some more SM-57 microphones in an overhead configuration to pick up the toms and cymbals.
Acoustic guitars, like all acoustic instruments, have the ability to change the timbre accordingto the recording axis and the position of the microphone. Most often you will use the direct output of the acoustic guitar coupled to a DI Box for interfacing to the console. Remember to set the ground-lift switch on the direct box to the position where you monitor the least hum. Again here is where the quality of the direct box you select will make a huge difference in the results. On those occasions when you can mic the acoustic guitar use a cardiod condenser microphone. Begin by adjusting the height of the microphone stand to the mid of the guitar strings. Position the microphone close to the front body of the guitar and near the twelfth fret to get the best results. Changing the mic position proximity and angle will affect the low frequency response.
A hint when feedback from any guitar is a problem or you are constantly adjusting the eq to keep things correct: Feed the pickup or direct out to the monitors, and feed the mic signal to the house speakers. That way you get minimal feedback from the monitors and natural sound in the house.
Some general tips on microphone usage to reduce the likelihood of feedback.
Most microphones are available in both wired and wireless versions. Every wireless microphone system must operate on a specific frequency. VHF systems are in very wide use right now, and are exceptionally affordable. UHF systems, which operate in the higher UHF frequency range, are better suited to multi-channel, multiple-frequency systems. Though they offer no benefit in terms of sound quality they do offer greater isolation from interference, which provides greater stability and reliability when using multiple wireless microphones.
With such a variety of microphone technologies there are some that lend themselves to specific applications within the church. The type of mic you will use on the Worship Leader depends on whether the person stays at the pulpit or wanders around. If they remain at the pulpit, install a lectern mic on the pulpit. This application also works well when you have different people making announcements or reading from scripture. Most manufacturers sell a Lectern Mic that swivels and has a shock mount to avoid thumps from contact with the pulpit. If the Worship Leader is active and moves about, use a wired or wireless clip-on lavalier microphone. The transmitter usually clips onto a belt and the receiver in the wireless system plugs into a mic or line input in the mixer. Locate the mic at chest height about 8 inches below the chin using the manufacturers microphone clip and route the cable inside clothing. Lavalier mics come in omni and cardioid pickup patterns. The omni microphone is best suited for this application as it’s design resists noise from clothing and has less proximity affect when the speaker turns their head.
Electric / Bass guitar can be an unruly monster to keep under control sometimes. Less is more when it comes to getting a good sound from a guitar amp mic placement. Take two Shure SM 57s and point the first one directly at where the dust cap meets the speaker cone; and point the second one at the speaker cone (not to the center of the speaker!) at a 45 degree angle from the first. The mics should be touching each other to ensure minimal phase difference. Now what you have is one mic that is picking up the brighter tone (straight on mic) and one that is picking up a darker tone (45 degree angled mic) of what the speaker puts out. This enables you to select either a warmer or edgier tone simply by changing the fader level relationship between mics, instead of having to immediately jump to the EQ.
If your worship team includes a Choir you may or may not want to include them in the house mix. If the choir is loud enough in the house of worship without amplification, you don't need to mike the choir unless you want to pick them up for recording or broadcast. Most manufacturers offer models designed specifically for choir micing. They are almost invisible, sound natural, and are available in black and white finishes. Use one microphone in the center of every 20 to 30 foot span. A choir of 30 to 45 voices should need only two or three mics. The fewer the mics, the better the gain before feedback. If the choir mics are used for sound reinforcement, place them close to the choir to minimize feedback: about 1.5 feet in front of the front row of singers, and about 1.5 feet above the head height of the back row. This placement tends to pick up all the rows of the choir about equally. Monitor feedback into choir mics is a serious problem because choir mics are far from their sound source. Try to keep the monitor level as low as possible.
Use as few microphones as possible. Each time you double the number of open microphones, the gain before feedback drops by 3 dB.
Turn down microphones not in use. This reduces the number of open mics, which prevents feedback and increases clarity. An automatic mixer (gated mixer) is a helpful tool here: it attenuates unused mics automatically.
Keep loudspeakers and microphones as far apart as is practical.
Keep microphones close to their sound sources - as close as possible, but no closer than necessary to achieve adequate volume before feedback occurs. Have the sound-system operator educate users to stay close to their microphones.
Use directional mics like cardioid, supercardioid or hypercardioid.
In conclusion, houses of worship require a wide range of mic choices and placements. Each sound source has special miking needs. But with some attention to those details, your application will provide a clear, natural sound that enhances the worship experience.
Experiencing Worship, The Study