Mixing Techniques
Choosing the Right Microphone
Microphone Types
The choice of microphone depends on the application that the microphone will be used for and individual preference. However, broadly speaking microphones fall into two main types:
Dynamic Microphone
A robust design which uses a thin diaphragm attached to a coil of wire arranged about a permanent magnet. Any variation in air pressure on the diaphragm will cause the coil to generate a minute electric current which then requires amplification.
Dynamic mics are relatively inexpensive, rugged and require no electrical power to operate. They are ideal for all-round high sound pressure levels (SPL) and tend to be used for live applications. However, they are not as sensitive to high frequencies as condenser types.
Condenser Microphone
A type of microphone which picks up sound via a thin, flexible diaphragm placed in proximity to a metal plate - as opposed to the rigid diaphragm-and-coil system used by dynamic microphones. They need power to operate - the most common source being +48v DC PHANTOM POWER.
Condenser mics are very sensitive to distant sounds and high frequencies. Because of this sensitivity they are often used in studio recording situations.
N.B. +48v Phantom power is used to charge the diaphragm and plate. It also supplies a small amplifier which boosts the small voltages generated by diaphragm movements.
Microphone Pick-up Patterns
A pick-up (Polar) pattern refers to the area(s) from which a microphone "picks up" its sound. It is important to choose the right pattern for your application, or you may pick up sounds from areas you don’t want or lose sound information you need.
Omni Pattern
The most basic type of microphone pattern.
A 360° polar response which picks up sound equally in all directions.
This pattern is ideal for picking up groups of vocals, audiences, ambient sounds but is most susceptible to feedback.
Cardioid Pattern
The ‘heart-shaped’ polar response of a microphone meaning that most of the sound is picked up from the front.
Used for most basic recording or in any situation where sound has to be picked up from mainly one direction. Dynamic cardioid mics are mostly used for live applications because they help reduce unwanted spill from other instruments, thus reducing the risk of feedback.
Hyper-cardioid
Similar to a cardioid pattern but with greater directionality. Used for live vocal microphones because it provides the greatest protection from unwanted spill and feedback.
Figure of Eight
Sound is picked up from the front and back but not from the sides.
This pattern is used mainly in studios for picking up two ‘Harmany’ vocalists, or solo vocalists who require some room ambience.