19/01/2015
Microphone Buying Guide
When you're shopping for new microphones, you'll encounter a wide variety of mic types spanning a vast range of prices. The glut of specs and features associated with the hundreds of available models can be confusing, leaving you with little basis for comparison aside from a microphone's price.
Sure, it's generally true that a mic's price reflects the quality of the sound it’s capable of reproducing. However, a little research will show you there are plenty of reasonably priced mics that are capable performers in many respects. In fact, many of these models copy the basic structures of microphones costing many times more. Understanding how various types of microphones function and what they’re intended for will help equip you to improve your live performances and enhance your recordings.
To help you find the right mic to match your budget and needs, this guide will cover the most important characteristics of the many different microphone types and models.
able of Contents
Sound Off: How Will You Use Your New Mic?
Check, Check: Understanding Microphone Specs
What Microphone Specs Don't Tell You
Types of Microphones and Their Applications
Application-Specific Dynamic Mics
Wireless Microphones
Condenser Microphones
USB Microphones
Microphone Packages
Microphone Accessories
Signing Off: Some Final Comments
Sound Off: How Will You Use Your New Mic?
The most important thing to ask yourself when choosing a microphone is how you plan to use it. Will you be using it onstage for vocals or to mic an instrument? Is it intended for home-studio recording? Or are you looking for something that can perform well in either situation?
You want to match the mic to both the environment you'll use it in and the gear you'll use it with. For instance, it might not make a lot of sense to spend thousands on a Neumann studio mic if you plan to use it for recording at home. The acoustics will be less than perfect, and since chances are are you don’t own high-end mic preamps, the Neumann’s virtues will essentially be wasted. A less sensitive and more affordable microphone might be a better choice.
If you want to find a single mic that will serve you both in the studio and on the stage, a number of models will fill the bill. The Shure SM57, for example, is a popular, go-to mic that gets extensive use in both settings.
Check, Check: Understanding the Specs
Getting some fundamental knowledge on microphone specifications and terminology under your belt will help you select a mic that best suits your needs. Here are the primary specs and terms you will often see in mic descriptions:
Polar Patterns
The polar pattern is the shape of a mic's field of sensitivity, or the directions from which it accepts or ignores incoming sounds. An omnidirectional mic responds to sounds coming from all directions. A bi-directional mic picks up sounds from east and west while excluding sounds from north and south. A unidirectional mic primarily hears sounds from one direction and excludes sounds from other directions.
Unidirectional mics are the most common type, and they come in three polar patterns:cardioid, supercardioid and hypercardioid. All three of these patterns reject rear-axis and off-axis sounds coming from behind the mic or from the sides.
The cardioid pattern is roughly a heart shape (hence its name), which makes the mic most sensitive to sounds from straight on and from the sides, but rejects sounds from 180 degrees opposite the direction the mic is aimed.
The supercardioid mic accepts a little more sound from a 180-degree field, but rejects more from each side. The hypercardioid allows yet more sound from 180 degrees but rejects more of the sound coming from 90 or 270 degrees.
Polar patterns are important when you are working in a noisy setting, such as when miking a vocalist in a band. Cardioid, supercardioid, and hypercardioid mics will tend to exclude all the sounds except the voice of the singer, thus preventing the signal from becoming muddied or producing feedback.
Multi-Pattern Microphones
Some microphones are multi-pattern. In other words, their polar patterns can be changed (e.g. from omnidirectional to cardioid) by means of a switch or by interchangeable capsules. This capability gives the mic added versatility in various settings.
Frequency Response
A microphone’s frequency response refers to the range of frequencies, from low to high, that a microphone will pick up. This range is referred to by its lowest and highest frequencies, measured in hertz. A microphone with a frequency response range of around 80 Hz to 15 kHz would make a good choice for a vocal mic. However for miking snares and toms, you would look for a range that starts lower, at around 50 Hz, and for a bass drum mic, you will want a low end of 40 Hz or even lower, down to 30 Hz.
Response Curves
It is important to note that frequency response only tells you the overall range a mic can reproduce. How it performs at different frequencies is another matter, and this performance is what gives a mic its character.
The shape of a microphone’s frequency responsiveness is called its response curve. Because it starts out at zero on the low end and drops off to zero at the high end, it takes the form of a curve when graphed. Within this overall curve, there will be peaks and dips in certain places that give the mic a certain character and make it more suited to certain applications. For example, a mic intended for vocals may have a spike in its upper midrange that results in smoother or more intelligible reproduction of voices.
Sensitivity and SPL-Handling Capability
Sensitivity refers to how quiet a sound the mic can detect, and it is expressed using different systems. Regardless of the system, it is perhaps enough to know that the lower the number, the more sensitive the microphone is.
SPL stands for “sound pressure level” and is expressed in decibels (dBs). It describes the maximum volume that a mic can handle, so, in a way, it is the opposite of sensitivity. This is important if the mic must deal with loud instruments such as drums. An average level is around 100 dB; a high SPL is 130 dB.
Proximity Effect
Proximity effect is not given as a specification, but is an important mic characteristic that is sometimes mentioned in descriptions.
Proximity effect causes bass frequencies to become more pronounced as the sound source moves closer to the mic. This is desirable for singers who "work the mic" to create effects. A recording engineer might select a mic with a strong proximity effect for close miking an instrument to bring out its bass tones.
Condenser mics generally produce more proximity effect than dynamic mics.
What the Specs Don't Tell You
The characteristics of a microphone involve more than just the specifications you read in its description. In fact, you will learn that some manufacturers fudge the numbers, so it can be hard to tell the difference, on paper, between a mic that costs $50 and one that costs hundreds or even thousands of dollars. However, the product’s structure, the kind of metals used and the precision of its manufacturing can all greatly affect its performance.
That’s why it's fair to say that price itself is a significant specification. Keep in mind that listening is the best way to really know the differences between a great mic and a lesser one.
Types of Microphones and Their Applications
Most microphones fall into one of two categories: dynamic mics and condenser mics – and these types are characterized by a number of important differences.
Typically, dynamic mics are more rugged than condensers, making them more suitable for on-stage use. Condensers, on the other hand, are more sensitive and more delicate, so they are most often used for studio recording. These are generalities however; there are dynamic mics that are often used in recording settings, and condenser models designed to handle the rigors of stage work.
Another distinction is the mic’s power requirement. Dynamic mics operate without a power source, while most condensers need a battery or phantom power supply (from a mixing board, preamp, or dedicated external power supply) to function.
Let’s take a closer look at the different microphone types to zero in on the best option for your purposes.
Dynamic Microphones
Dynamic microphones use an inductive coil connected to a diaphragm and placed within the field of a permanent magnet. As the diaphragm moves, it moves the coil, thus varying the voltage the coil produces. These subtle shifts in output voltage shape the mic’s output.
These mics are usually quite rugged, and have high SPL-handling capability. Most have internal shock mounting to allow hand use, and their polar patterns reject off-axis sounds. These are all reasons that dynamic mics tend to perform well in live sound situations, though some also are used regularly for recording. The Shure SM58 has been both a studio and stage staple for many years.
As a group, dynamic mics also are relatively affordable, and many of the big-name mic manufacturers have economy-series mics that give you great performance for a low price.
