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Searching for the right microphone for your needs can be a daunting task, but it can be made more challenging when you enter the search without basic knowledge of what you’re looking for.
When people are looking for the right mics for them, the most important thing to know is whether you’re looking for a dynamic microphone or a condenser microphone. Once you know what characteristics distinguish one from the other, finding the perfect microphone for your needs becomes so much easier.
While there are so many dynamic mics on the competitive microphone market today, you may be curious about how exactly the dynamic mic works so you can pick the best one for you. If you are wondering what a dynamic microphone is and whether it’s suited for your purpose, we’ve laid out the basics and everything you need to know about how dynamic microphones work.
In its most basic form, dynamic microphones are best for live events where the volume on the stage is too high or for recording musical instruments like snare drums and guitar amps due to the dynamic microphone needing more electrical energy to vibrate their diaphragm.
The diaphragm of the dynamic microphone is its most essential part, with it being nothing more than a light and thin film which is connected to a coil. This diaphragm vibrates with sound, which in turn moves the coil. Additionally, the presence of a permanent magnet next to this moving coil produces an electrical signal.
Dynamic mics work on the electromagnetic principle. Electromagnetic induction is a key factor in dynamic microphones and means that a dynamic microphone must have a magnetic structure that provides a magnetic field, an electrical conductor in which voltage can be taken with lead wires and a mechanism that allows relative movement between the conductive element and the magnetic field for the electromagnetic induction. In simpler terms, electromagnetic induction means that when metal passes through a magnetic field, an electrical current is transported into the metal.
The most common polar patterns for microphones include cardioid mics, super-cardioid mics, omnidirectional mics, bidirectional mics, and shotgun mics. Most dynamic mics are cardioid mics, meaning that the microphone is made to capture from one side of the capsule. Dynamic microphones with a super-cardioid pattern are also preferred for many live vocals since they are still more directional than cardioids.
Frequency response refers to the range of frequencies that a microphone can distinguish and replicate. Sound waves vibrate at precise frequencies, and all models have a unique sound produced, characterized by their receptiveness to certain frequencies.
For example, some models are sensitive to lower frequencies or “darker sound” while microphones with “brighter sound” are more attuned to higher frequencies.
The proximity effect is an increase in low bass frequencies the nearer a mic is moved to a sound source. In other words, the proximity effect means that the nearer you are to a microphone, the more low frequencies it will capture and vice versa.
A polar pattern illustrates from what direction a mic will be sensitive to picking up sound and from what direction it will ignore the sound. At lower frequencies, dynamic microphones become less directional, and at higher frequencies, they become more directional. As mentioned previously, there are several types of polar patterns for microphones.
Sound pressure level indicates the loudness dynamic mics can manage before they distort. Dynamic mics are best at dealing with the loudest sounds before succumbing to distortion.
Now that you have your most basic answer to the question, “what is a dynamic microphone?”, you should also learn the two types of dynamic microphones so you know exactly what will capture the best sound for your recording purposes.
Moving coil microphones are the most commonly used type of dynamic microphone. These types of dynamic mic utilize a coil of wire attached to a diaphragm within a magnetic field.
When the diaphragm moves due to sound, it makes the coil vibrate and in turn creates an electrical signal. The oscillation of the electrical conductor within the permanent magnet field causes an AC voltage to be produced across the coil via electromagnetic induction. This AC voltage is taken via lead wires as the mic’s audio signal.
Ribbon microphones are extremely sensitive dynamic microphones designed to be used for atmospheric types of sounds, such as jazz, folk, blues, or more restrained vocals.
Active ribbon microphones contain a thin ribbon of aluminum foil situated between two magnets. When acoustic energy or sound waves hit the ribbon, they generate an audio signal. While most dynamic mics are great for live events, active ribbon mics are best used in the studio. It’s always best to tilt active ribbon mics slightly off-axis, distance the vocalist from the ribbon mic, and use a pop filter.
While there are many different microphone types out there suited for different recording purposes, there are two major categories: dynamic and condenser microphones. In simple terms, while condenser microphones are suited for picking up detailed sound in a controlled environment like a studio recording, dynamic microphones are more suited for live performances where volume levels are higher and there’s a lot more background noise.
Dynamic microphones are the best choice for picking up specific sound coming from a noisier environment, such as concerts and spaces with a crowd, and when you need something wireless that doesn’t require external power or phantom power. You can also use a dynamic microphone, like active ribbon microphones, when recording vocals or musical instruments that don’t require as much sensitivity such as brass instruments, some acoustic guitars, snare drums, or loud vocals.
On the other hand, condenser microphones are extremely sensitive, are best used to record quieter sounds, and are often powered by phantom power. Condenser mics are perfect for delicate sounds or instrumental nuances in a controlled setting. However, since the sound pressure level of condenser mics converts sound to such a high level, they’re susceptible to picking up frequency responses and can pick up popping noises and breathing sounds, hence the importance of knowing what kind of mic you need for what kind of setting you’re working in.
While a condenser and dynamic mic type might record high frequencies versus low frequencies and sound coming from different settings, you’ll be able to rely on the fact that they both typically accommodate an XLR cable or a three-pronged cord that transports electrical signal.
Unlike condenser microphones, dynamic microphones are not very sensitive, are very resistant, do not require phantom power, batteries, power supply, or other external power sources, and support high sound pressure levels.
Moving coil microphones, like the Shure SM58, are your best choice when recording sound in a noisy environment, while ribbon microphones are fantastic for a studio setting when you’re recording louder vocals. However, while ribbon microphones can certainly be used for quiet studios and are less suitable in places with uncontrollable sound, we’d recommend condenser mics over ribbon microphones when you need something that picks up quiet sound like for podcasts, live streaming, and similar situations.
With so many microphone models out there in the market, it can be difficult to figure out exactly what type of microphone fits our specific needs, and we might also be constantly asking the question “what is a dynamic microphone?” while on the hunt for the perfect type.
However, knowing the difference between condenser and dynamic mics is a very good place to start. By understanding what makes up a dynamic microphone, whether you need moving coil microphones or ribbon microphones, even beginners can know what produces the best sound for live occasions, recordings in settings where noise cannot be controlled, or studio recordings for brass instruments or other loud instrumentals.