array microphones

An array microphone (sometimes called a microphone array) is a microphone system whose output is obtained by array processing of the signals from at least two individual microphones.

Some array microphones are capable of amazing things.  For example, they can provide a sharp polar pattern that can be electronically steered toward whomever is speaking around a conference-room table.  And large array microphones can provide very high directivity that facilitates capturing sound at long ranges.  But those types of array microphones are neither easy nor cheap to build.

However, array microphones don’t have to be complex or expensive to be useful.  Specifically, simple array configurations can be used to make studio microphones that rival the performance of commercial microphones costing much more, and that’s going to be the focus of most of the posts in this category.

Small arrays can provide two benefits in a studio microphone application:

  • An array can have a higher Signal-to-Noise Ratio (SNR), or equivalently a lower self-noise, than that of the individual microphone elements.  So, a small array of inexpensive microphone elements can be used to make a studio microphone with lower self-noise than expensive commercial units.
  • An array can be used to electronically synthesize all of the main polar patterns used in studio microphones: cardioid, supercardioid, hypercardioid, and bidirectional.

Even better, both of the above benefits can be combined to yield a low-noise studio microphone with an electronically switchable polar pattern.