When picking out a microphone, the first thing to decide is what type of microphone you need. If you’re a vocalist who records in studios, a condenser mic is a smart choice. However, for anyone who performs live, a dynamic mic should be your go-to microphone. Time to break down the various microphone types and when to use them.
Editor’s note: This article was updated on March 23, 2020 to include links to additional information on USB microphones.
Which microphone types are best for certain needs?
Just how there are multiple classifications of headphones—open, closed, over-ear, on-ear—there are a multitude of microphone types. Your needs will dictate whether you should buy a dynamic mic or condenser microphone. Likewise, perhaps you’ll want one with multiple recording patterns as opposed to a one-trick pony, so to speak.
Live musicians should get a dynamic microphone
If you walk into a music store and ask about different microphone types, the clerk will likely present you with a dynamic microphone. This variety of microphone lends itself nicely to vocals, drums, and general instrumentation. Live performers prefer dynamic mics for a few reasons: they’re durable, affordable, and can withstand plenty of loud noise before signal distortion sets in. Many have a built-in high-pass filter to attenuate sub-bass frequencies. The veritable Shure SM58 is dynamic and a great option for open mic performers due to its high value, low-cost nature. If you want a more stylish option tuned for vocal pickup, the Shure 55 SH Series II may be more up your alley.
Shure SM58 microphone demo:
This type of microphone is simply built, just like dynamic drivers in headphones. A coil, surrounded by a magnet, is attached to the back of a diaphragm. As soundwaves from your voice hit the diaphragm membrane, it moves, pushing the coil back and forth. This dynamic movement interacts with the stationary space between the coil and magnet to create a minute voltage signal, thus converting soundwaves into an electrical signal to then be projected through your amplifier.
Condenser microphones are great for studios
Another breed of microphone is the condenser mic. These are excellent for recording nuanced sounds like string and wind instruments and are preferred for studio recordings. They require external power, be it phantom power or a preamp. They’re more delicate than your average dynamic microphone. Therefore, they require a tame, controlled setting. Due to their sensitivity, your recordings will benefit from a shock mount and pop filter. Of course, there are exceptions to every rule: shotgun condenser microphones are used on TV and movie sets, so as to pick up all dialogue. Fellow SoundGuys Editor Adam Molina prefers the Rode NT1-A as his daily workhorse.
If you’re working from a home studio or office, and don’t want to fuss with an audio interface, there are all sorts of great USB condenser microphones—perfect if you’re stuck at home using video chat apps for meetings during a pandemic.
Shotgun microphone demo:
Now that we know what environments condenser mics shine in, let’s quickly break down how they work. Rather than using moving a magnet and moving coils, these use capacitor plates which are constantly charged from an external power source. The front plate is made from a malleable material and is comparable to a diaphragm used in dynamic microphones. Soundwaves hit the front plate which then vibrates. This slight movement changes the capacitance between the front and rear plates and converts it into an electrical signal.
Ribbon mics make voice recordings shine
When I think of a Transatlantic accent, I picture a man in a suit with large lapels, tightly combed hair, standing behind a rectangular ribbon microphone. The ribbon mic was invented way back in the early ‘20s and is less prevalent today.
This type of microphone is great for recording voices and had a higher resonant frequency than microphone diaphragms back in the 1920s. Upon inception, they were remarkably fragile but have since become more rugged. They usually have a bidirectional polar pattern, meaning they equally register sounds from the front and rear.
Ribbon microphones aren't as fragile as they once were but dynamic mics are generally tougher, still.
As the name suggests a ribbon microphone uses, well, a ribbon. It’s suspended between a magnet’s oppositely charged poles. As it vibrates between said poles, a voltage is created. Fun fact, the velocity of the ribbon’s movement is directly proportional to the induced voltage. This signal is then converted and transmitted for output. If you need a microphone to accurately produce high-frequency sounds, this is a great option so long as you have a phantom power supply.
Tube microphones have a passionate following
These condenser microphone use a vacuum tube to amplify the signal from the recording capsule. They require more than 48V phantom power, but it’s rare to find a tube microphone that doesn’t include an external power supply. Tube microphones are great for voices, too, as they tend to emphasize bass frequencies, making vocal fundamental frequencies more perceptible. There’s an ardent fanbase surrounding tube microphones, but realistically, a general condenser mic will serve just as well for most instance, and be more accessible.
What you should know about microphones
Now that you have an idea of the microphone types, let’s go over polar patterns. These determine from which direction, or directions, a microphone registers sound. Here’s the skinny: cardioid mics have a heart-shaped pickup pattern are generally forgiving with regards to where the microphone is placed. This pattern has some off-axis rejection but will still capture room ambiance. It’s one of the most popular patterns for consumer microphones. If you want to learn more, Chris has an in-depth breakdown of various recording patterns.
Frequency response and sensitivity
Headphones, microphones, and speakers all have a specific frequency response. This denotes how well something can reproduce an audio signal across a specific frequency range. A commonly used frequency range is 20Hz-20kHz; these are the lowest and highest frequencies the human ear can register.
A perfect frequency response looks completely flat on a chart, but you won’t actually come across this in the real world. Not all vibrations are transmitted as electromagnetic signals, no matter what type of microphone you’re using. This means some frequencies may be less or more audible, depending on the microphone. When visualized like in the chart above, a louder frequency range appears as a bump, while a quieter one dips.
Sensitivity is a little different. It just refers to how easily the mic picks up sounds. A more sensitive microphone is able to register quieter sounds than a less sensitive one. Take the Shure SM58, it has a sensitivity of -54.5dBV, meaning -54.5dB is the quietest sound it can relay.
There are common recording problems that newbies and professionals all run into. If you happen to be recording inside, be it in a full-fledged studio or your DIY blanket fort, there are easy ways to mitigate in-room echoes. Now, recording outside — that’s a completely different beast.
If your space has a lot of reflective surfaces (e.g. hardwood), you’ll need to go to great lengths to reduce echoes. Soundproof foam panels are an effective way to do this and don’t require much effort to install. For those with tight budgets, look into bass traps for the corners. As you may expect, corners amplify echoes. Those working from home should record from the innermost room. This will be an effortless way to mitigate street noise.
Relatedly, you can easily get rid of plosives and fricatives with a pop filter. These are the unwanted pops and hisses that creep into recordings. A pop filter shields the mic capsule from the expulsion of air that leaves the mouth with words like “papaya.”
Demo of plosives:
Demo of fricatives:
Prevent the proximity effect
The proximity effect is most often experienced when we take phone calls but can impact all microphone types. As you speak closer to a microphone, especially a cheap one, low-frequency sounds are amplified. While this isn’t the end of the world for phone calls, it can really ruin a recording and force you to spend more time editing than you initially intended. Speaking six inches from the microphone helps to reduce this effect. Additionally, try your best to remain still while recording. Swaying too far forward or away exacerbates its presence.
While we’ve just brushed the surface of how each microphone works, you should leave here with a better understanding of microphone types and when to use what. Whether you’re looking to record a podcast, videos for your YouTube channel, or people in various environments, we have you covered.