Considerations for Selecting Microphones
By: Scott Pisani

As a few minutes of surfing the Internet will reveal, there are literally hundreds of different microphones from dozens of manufacturers available today. How does one pick the exact microphone he or she needs from so many options?

The first step is to decide on a budget. You can find microphones ranging in price from just a few dollars up to thousands of dollars. And, much like the logarithmic laws governing the principles of sound, a $1,000 microphone is not necessarily a hundred times better than a $10 microphone.

Often, top-dollar microphones serve very specific purposes that go far beyond what might take place within the walls of a typical house of worship. For most applications, a low-priced to mid-priced microphone is perfectly fine for clergy, musicians, lectors, etc. A microphone that is priced too low could fall under the "buyer beware" category, but, typically, if it is from a trusted supplier, it should be adequate.

With budget in hand, there are two factors to consider with every microphone purchase: dynamic or condenser, and wired or wireless.

Dynamic vs. Condenser
Dynamic and condenser refer to the technology within the microphone that converts the audio signals to electronic signals. Dynamic microphones work through electromagnetic induction. Simply put, this means a coil is placed within a magnetic field. The movement of that coil from the outside sound stimuli creates a current proportional to the sound level and frequency, and that current is sent on to the amplifier to be once again converted to sound at the output.

Condenser, or capacitor, microphones work through the placement of a charged diaphragm and plate very close to each other. The diaphragm is moveable, and the plate is fixed; when sound enters the microphone, it moves the diaphragm proportional to the sound level and frequency. The change in distance between the two plates creates a current that is then sent on to the amplifier to be converted into sound again at the output.

What's the difference between the two types? Dynamic microphones tend to be less expensive and more versatile in applications. Condenser microphones tend to be more sensitive than the typical dynamic microphone, and thus are better at picking up lower or softer sound sources, but it also means they are more expensive.

So, how do you choose? There's no clear-cut answer here. The first variable is which one better fits into the budget. The second variable is the application anticipated. For the clergy to perform a mass or do a reading, a dynamic microphone is more than fine. Even for the majority of basic musical efforts, a dynamic microphone will serve. If high sound clarity and quality is a greater concern, that's when you would look at the condenser microphones. It's also very likely, in larger congregations, to have a mixture of both.

Wired vs. Wireless
This is self-explanatory. Wired microphones have an actual wire that connects the microphone directly to an amplifier. A wireless microphone utilizes a specific frequency to transmit, in the same method a radio station would, to a wireless receiver.

There are two basic types of microphone wires: balanced and unbalanced. Balanced lines are preferred to their unbalanced counterparts, as they utilize methods to reduce interference in the wire and thus can be used over longer runs. XLR is the most common type of balanced connection. Also, 1/4" phono plugs are the most common unbalanced connection. The types of microphone inputs on your amplifier will determine which one you should use.

The two most common forms of wireless microphone transmissions are via VHF and UHF. The VHF band is located in the frequencies between 30 and 300 MHZ. UHF microphones are allowed to use frequencies between 470 and 806 MHZ. UHF is the more popular of the two, as the wave of the broadcast signal is smaller, meaning you experience less dead spots than you might with VHF. This is done through diversity reception, meaning that the size of a UHF wave is such that a UHF receiver can utilize two antennas built into a single box to ensure that one of the antennas is always within the broadcast area. VHF waves are too large to allow this in a reasonably compact box.

What's the difference between the two methods? This may or may not be a disadvantage depending on the application, but with wired microphones, you are limited in where you can roam; with wireless microphones, you are only limited by the range of the microphone and receiver. Wireless microphones also eliminate cable connection breakage problems that tend to arise over time with wired microphones that are heavily used.

Wired microphones have their advantages as well. You can typically run a balanced XLR cable for a longer distance than most UHF microphones can broadcast to a receiver. Wireless systems are also susceptible to interference from outside sources, since the bands they broadcast on are public domain and shared by other wireless microphone users and other wireless applications, whereas a properly shielded wired microphone cable is great at preventing interference. Wireless systems also require frequent battery replacement or charging. Finally, wireless microphones and receivers are usually more expensive than their wired counterparts.

So, how do you choose? Again, there's no clear-cut answer here. Depending on budget, most congregations will utilize a combination of wired and wireless microphones. Because wireless microphones leave the hands free, the majority of clergy prefer to use these, since it lets them perform their ceremonies unhindered and also allows them to move about freely. Other participants, however, could easily perform their tasks with a wired microphone kept in a set location, such as a lectern or altar. Musicians and the choir, unless they have a reason or desire to roam, would have no problems using wired microphones.

What we have shared so far is fine if you have one supplier you always use and do not have the time or interest in going into an in-depth comparison or analysis of one specific microphone vs. another, but not everyone is always so dedicated to their vendors. There are several specifications, so it helps to understand to figure out what's so special about any given microphone or to decide if it's right for your specific purpose.

Directionality
In your research, you should come across one of the following terms: unidirectional (Subcardioid, cardioid, hypercardioid, or line), bidirectional, and omnidirectional.

These refer to the directionality. Unidirectional microphones receive sound from one direction, bidirectional microphones receive sound from two directions, and omnidirectional microphones can receive sound from all directions.

Unidirectional microphones have several subclasses. Subcardioid microphones generally have the widest reception range, and line microphones would have the smallest. Cardioid microphones are the most commonly used as the reception, or polar, pattern is the best suited for typical microphone use.

Frequency Response
When a frequency response is listed under a microphone's specifications, this reflects the lowest to highest frequencies that this piece of equipment is capable of efficiently converting to electrical energy. You may see this denoted in a format like 50 Hz to 16 kHz. You could also see a decibel variation noted with that range, such as -3 dB. For the specific range example I gave, that means that the 50 Hz and the 16 kHz both reflect a 3 decibel variation below nominal. -3 decibels is a standard which reflects a 50 percent loss in operating efficiency. 50% might sound like a lot, but keep in mind that the average person's ear can not distinguish variations of 3 decibels or less.

Your application will also affect what type of frequency response you want in your microphone. There can be advantages to buying a microphone with a smaller range. For example, if you know that the microphone will only be used for talking or reading, you might want the limited range so that the microphone does not pick up unwanted background noises. The average person's voice falls within a 125 Hz to 5 kHz range. Just be careful not to use that small range microphone for your cantor or musicians.

Microphone Design
The design of the microphone you choose will depend on the specific application for which you intend to use it. The majority of all microphones sold will be one of the following types:

* Handheld microphones are most often used by singers or whenever there would be a reason to pass a microphone around.

* Lapel microphones are almost exclusively wireless and would be most utilized by the clergy or someone who plans to wear the microphone for a while.

* Tabletop and gooseneck microphones are similar, with the primary difference being that tabletop microphones come with their own base, whereas gooseneck microphones need to be secured. Gooseneck microphones have greater versatility for the purposes of a house of worship since you can install them onto an altar or lectern.

* Hanging microphones can be placed above the choir, or musicians, or even above the altar.

* Boundary microphones are placed on the ground and mostly used for hands-free performance purposes.

These are only the most common designs of microphones. There are many other designs available, most designed for specific applications.

There is a lot involved when deciding on what microphone to purchase. If you are ever in doubt, speak to an expert. There are plenty of companies that specialize in selling audio equipment to houses of worship, and even more companies that specialize in audio sales period. Regardless, hopefully this article has provided enough of a start to get you on your way to being comfortable when making your next microphone purchase.

Scott Pisani is the audio product manager at Speco Technologies, www.specotech.com, a New York-based manufacturer of audio, video, security and access products.

Sidebar
Evaluating Microphone Options for Pastors
By Gene Houck

There certainly has been a move from the standard lapel mic to a small low profile headset mic for pastors. It may surprise you; however, how many churches still prefer a podium or pulpit mic. Here are a few pointers to either help you decide which way is best and/or to help you maximize performance.

Headset Microphones
The most popular headset microphones for pastors over the past few years have been small discreet single ear piece microphones. These mics are lightweight, very low profile and come in omni patterns. The omni pattern mic allows for the broadest pickup pattern, and it helps to not require the element to be directly in front of the speaker's mouth, thereby reducing plosives or popping. They can be ordered in either wired versions or for wireless application as well. As discreet as the single ear piece is, there can be some challenges with the element of the mic migrating away from the desired position. There also can be, on occasion, some durability issues with a single ear headset. A big advantage of headset mics is that they pickup the speaker no matter if he turns his head far left or far right. There is no fading in and out that can sometimes occur with a lapel microphone.

Lapel Microphones
The lapel microphone can be an effective solution for a pastor. They are typically a bit more affordable than the headset counterpart. The key is proper placement. It is important to not have the mic too close to the chin so as to not miss phonetics, and it is equally important not to have the mic so far away as to create potential feedback issues and drop outs. The proper position of the mic is centered and one hand spread away from the chin.  

Podium or Pulpit Microphones
Before lapel and headset microphones, there was the podium mic, and it still is the favored choice for many pastors today. Besides allowing a pastor to have an area to keep notes and a Bible, it also avoids a pastor from having to wear a mic. If you use a podium mic, take the effort to set up a proper gain structure that will best allow the pastor some movement and animation.  Tell your pastor not to lean up to within 1" to 3" from the mic. There can be some nasty pops if too close to a podium mic. Understand that doubling the distance of the speaker to the microphone will drop the sound level by 6 dB.

The answer is setting the gain structure with a large enough pick up area so that the speaker can communicate naturally with their own personal style of gestures and every word is picked up nicely.  

Gene Houck is the national sales manager for Audix Microphones, www.audixusa.com.

Product Roundup

Long's Electronics
Sound systems contribute to making a worship service more enjoyable. Dynamic, vibrant sound always starts with microphones.
* Wireless microphones add the benefit of mobility to the person speaking.
* Wireless handheld vocal microphones add a more pleasing aesthetic to singing performances.
* Choir microphones ensure that the member's voices are clearly heard on recordings made during the worship service.
* Wireless systems are available for guitars that allow them to be introduced into the house sound system.
Long's Electronics offers a wide variety of microphones for churches.
www.longselectronics.com

AmpliVox Digital Travel Audio Partner
AmpliVox sound systems announces the next generation of the Travel Audio Pro. The Digital Travel Audio Partner is a unique and revolutionary all-digital portable public address system with remote control. The system features:
* Built-in CD with pitch control
* Ability to deliver 250 watts to an audience of 7,500, in a room up to 25,000 square feet
* SD slot
* Built-in UHF wireless with 200 foot range
The system comes with an AC Power cord and two 12-volt rechargeable batteries for up to 10 hours of run time.
www.ampli.com

Audio-Technica's AT2010
The new AT2010 cardioid condenser vocal microphone brings studio-quality articulation and intelligibility of Audio-Technica's 20 Series to the church, for crystal-clear vocal performances. Featuring the same 16 mm low-mass diaphragm found in the AT2020 side-address studio condenser, the AT2010 excels wherever articulate vocals are needed. The system features:
* An extended flat frequency response (40-20,000 Hz)
* Superior transient response resulting in smooth, natural sonic characteristics
* Fixed cardioid polar pattern allowing isolation of the desired sound source and reducing acoustical feedback from monitors or other sources
www.audio-technica.com

Sennheiser Evolution from ProAVMax
The Sennheiser Evolution EW112G2 Wireless Microphone System with lapel microphone is ideal for stage productions and presentations. The unobtrusive clip-on omni lavalier (lapel) microphone is virtually invisible and has excellent feedback rejection. The extremely small body pack transmitter as well as the rack-mount receiver feature nine frequency banks with four frequency presets each for direct channel selection and are ready for immediate selection.
The Sennheiser EW112G2 Wireless Microphone System includes:
* 1 x Body Pack Transmitter
* 1 x ME2 omni-directional lavalier (lapel) microphone with clip
* 1 UHF frequency agile rack-mountable receiver. 
www.ProAVmax.com

Audix Micros
The Audix Micros Series offers the world's smallest condenser microphones with integrated preamp and detachable cable. The Micros, in conjunction with the MicroBoom, are popular for choir and overhead miking as well as podium or pulpit miking. The Micros feature:
* Newly designed circuitry with immunity from RF interference caused by cell phones
* Frequency response of 80Hz – 20kHz or 40Hz- 20kHz
* Ability to use us hanging mikes or portable overhead miking 
The MicroPods consist of 6-inch, 12-inch, and 18-inch goosenecks along with the M1250 microphone for podium application.
www.audixusa.com

Maryland Sound and Image
Maryland Sound and Image sells high-end, professional sound microphones to meet the needs of any church. The company carries top brands such as:
* Sennheiser
* Shure
* Beyerdynamic
* Audio Technica
* AKG
Visit their Web site for pricing.
www.marylandsoundandimage.com