Dynamic and Condenser Microphones

In this help page we will explain the main differences between the two main types of microphone and also explain some of the terminology surrounding microphones. This will allow you to make the right decision when choosing your next microphone and make sure it is right for your purpose.

Dynamic Microphones

Dynamic microphones are the most common type you’ll see - they’re the standard handheld “Karaoke” type. A diaphragm is attached to a moving coil which is moved by the sound wave entering the microphone. This moving coil sits round a magnet, which using the “motor effect” induces a current into the moving coil of wire. This current is proportional in strength and frequency to the original sound wave. 

Because they are so simple in design, they are also very robust. This makes them ideal for using live on stage or for recording very loud sounds such as drums or guitar amplifiers that would damage some more sensitive microphones. They are, however not sensitive enough to pick up or record low volume sounds such as cymbals, acoustic guitars or quiet vocals. 

Condenser Microphones 

Condenser or capacitor microphones are more commonly used in a recording studio for vocals etc, but they will be seen on live sound set ups for overhead drum miking and acoustic guitar pick up. They work in a slightly different way to dynamic microphones, instead of a coil and magnet; they have two electrically charged plates (one positive and one negative). One of these plates is fixed and one is able to move (acting as the diaphragm) as the sound wave hits the diaphragm it changes the distance between the two plates, creating a changing voltage that is proportional to the original sound wave. 

Because the mass of the moving part in this type of microphone is less than the moving coil inside a dynamic mic, they are able to reproduce much more detailed and low transient sounds.  However due to this, they are easily damaged both by rough handling and loud sounds. 

Condenser microphones need a power supply to create the charge between the two plates; this is usually provided through the mixing desk and is known as phantom power. It is most commonly +48V. This supply can also be provided by batteries inside some condenser microphones or an external power supply if your mixer does not have this capability. 

Microphone Terminology

Polar Patterns

The term polar pattern is used to describe what areas or direction the microphone picks up sound from. They all have different uses. Cardioid pattern microphones pick up from only one side of the microphone; this is useful in live sound applications for reducing the risk of feedback and in recording situations for reducing spill where multiple musicians are being recorded at once. 

An omnidirectional microphone’s on the other hand picks up sound theoretically evenly from all sides on the microphones, they are used to capture a room’s ambience or for example when a group of singers needs to be recorded from a just a few microphones. 

A few polar patterns are shown below:

 

Frequency Response

The frequency response of a microphone tells you how well it picks up different frequencies or pitches of sound. This is useful when picking which microphone is most suited to your purpose.  For example when miking a bass drum, a microphone with a good low frequency response is needed, but if you’re miking a mandolin you’ll need a microphone with a better mid – high frequency response. 

Frequency response is usually plotted on a graph showing the relative level at which the microphone picks up sound depending on frequency. If you want a truly accurate recording that has not been coloured in any way by the microphone the flatter the response the better. 

Equivalent Noise Level

All microphones will create a slight amount of distortion to the signal the equivalent noise levels tells us how much noise or background hiss the microphone adds to the signal when picking it up.  This is generally quoted in dBA, decibels weighted for the response of the human ear. Generally the lower the value the better.