(a.k.a. Omnidirectional vs Unidirectional)
This FAQ will answer many frequently asked questions when considering
whether you need to use Binaural, Cardioid or Hyper/Super Cardioid mics......
Cardioid microphones are Uni-directional microphones and pick up sound mostly in the direction you point them. They cannot be used to make binaural recordings, but can, of course, be used to make stereo recordings. Because of this directionality, they have certain advantages over Omni-directional mics in some situations.
2- How can a Binaural mic be used to make a stereo recording?
In addition, when you need a good sounding mic and have a limited budget, Omni mics would be a better choice as cardioid mics of the same quality cost 2 to 3 times as much as omnis.
5- When is it advantageous to use Cardioid mics?
Since Cardiods are directional mics, they will greatly reduce excess reflected sound coming at the mics from all over the venue. They do a good job of reducing unwanted audience noise from the sides are rear. While they can be used up close with excellent results, they excel over Omni mics when recording from a distance. In fact, there are different levels of directionality available, including Sub-cardioid, (regular) Cardioid, Hyper-cardioid and Super-Cardioid (sometimes called shotgun) mics. In general, the further you are from the sound source, the more directional the mic should be.
Cardioids are also the preferred mic to use on stage for sound reinforcement
applications, since they are less likely to feedback through a PA system.
On the downside, cardioids are more susceptable to handling and wind noise,
so if you can't secure your mics firmly or have to record in windy situations
and don't want to use large windscreens, omni's would be a better choice.
Both Omnidirectional and Cardioid mics are capable of recording very loud music. There are other considerations, outside of the scope of this FAQ. See our battery module FAQ for more information on this subject.
If you are going to be very close to the sound source, omni's or Cardioids would work well. However, if you are going to be a little further back (about 20 to 75 feet from the sound source), Cardioids would be a better choice. If you will be even further back, Hypercardioids or Shotguns would be the mic of choice. Some mics, like the Sound Professionals Premium and Slimline Cardioids have interchangeable elements that offer these choices without having two different sets of mics for different purposes.
No, but all of this can be quite confusing. The reason mini omni mics are sometimes called binaurals is that over the years, in the industry, these little omni mics have simply become known as "Binaurals".
Really, what they would be more accurately called is "dual channel miniature omnidirectional microphones that are capable of making binaural or stereo recordings", but we might grow old having to say that each time, so we just shorten it to "binaurals".