Not Every Microphone's a Hammer
What you need to know about dynamic, condenser and ribbon microphones.
What do I mean by not every microphone's a hammer? It's mainly a spin on the title of a book I read by Adam Savage called Every Tool's a Hammer. Great book. I would definitely recommend reading it. But I also believe this title perfectly represents how we should view microphones.
In extremely simple terms, a hammer is a tool used to drive nails into wood. As we know, hammers come in all shapes and sizes but they all accomplish the same task using the same method. A microphone is just a tool we use to capture sound. Similar to our hammer example; microphones also come in all shapes and sizes. Although, while all microphones accomplish the same task, the method by which they do so can vary greatly. Thoughtful consideration needs to go into choosing the right microphone for each specific job.
Consider these questions as you read through this article: Why use one type of microphone over another? How does a microphone have a sound of it's own? Is the microphone I'm currently using the right choice for the job?
In this article, I'll be discussing the three different types of microphones, some of their main uses, and a few pros and cons of each. Let's first start with the basics.
What is a Microphone?
A microphone is a transducer. A transducer is a device that converts one form of energy to another. A microphone converts sound waves (sound energy) into an electrical signal (electrical energy). This electrical signal can then be manipulated by what we call analog gear, such as a mixing console, or it can be converted once again into binary data that can be understood and manipulated by computers. This binary data is then converted back to an electrical signal that can be transformed by a speaker into sound waves.
All microphones are designed to perform this "basic" function, but the method by which they do so is not always the same. This is where we get our three different microphone types: dynamic, condenser and ribbon.
Considered to be the most common microphone type; the dynamic mic is a well-rounded tool that's perfect for the majority of circumstances. They're affordable, reliable, and work well on loud sources and in noisy environments.
Most dynamic mics are extremely durable and can sometimes be used as a literal hammer. Though definitely not recommended.
A dynamic mic captures sound via a "moving coil" architecture. Inside the capsule, there's a fixed magnet surrounded by a metal coil. Sound pressure forces the metal coil to move around the magnet causing electromagnetic induction, which generates an electrical signal. There's a great explanation of how this design functions over at Teach Me Audio. Click HERE to learn more.
Dynamic mics are commonly used during live performances and in studio environments. I often recommend that podcasters use a dynamic mic if their recording environment suffers from unwanted noise problems. They offer great noise rejection properties due to their low sensitivity and directionality. Dynamic mics can lack in clarity compared to most condensers and ribbons. If you're looking to capture a really clean and open sound, I would avoid a dynamic.
Can handle high sound pressure levels
Passive (no power needed to function)
Great noise rejection
Limited frequency ranges
Require a significant amount of gain
Audio Engineers will drool over a nice condenser mic. The majority of condenser mics are found in studios, but there are a few variations that make there way into live events. These microphones are extremely sensitive and often very expensive, which is why they're not ideal for most live environments.
To keep things simple; a condenser mic captures sound by using two electrically charged plates. One plate is fixed at the rear of the capsule, while the other plate, also known as the diaphragm, is suspended in the front of the capsule. There is a slight gap between the two plates. Sound waves push the diaphragm closer to the back plate. The space alteration between the plates is converted into an electrical signal. There's a great explanation of how condenser microphones work over at Neumann's website. Click HERE to learn more.
Condenser mics need power to operate. The electrical current needed to charge the plates in the capsule is called Phantom Power, which is displayed as +48V on audio interfaces and consoles. Some condensers may also run on an internal battery or some other external power source.
Large diaphragm condenser mics can be built with a solid state or tube infrastructure. Tube condensers are more expensive, require occasional maintenance and generally have a "warmer" tone compared to solid state condensers.