Every microphone has a characteristic polar pattern that determines how well it accepts or rejects signal coming from various areas around the microphone. For example, omnidirectional mics accept all signals regardless of wherever those signals originate (in front of the mic, behind it, to the side, etc.). In contrast, directional cardioid mics are specifically designed to accept mostly signal coming from directly in front, and to reject signal coming from behind or from the side. The cardioid pattern is utilized by the QTOM (as shown in the illustration below). For this reason, the QTOM excels in environments where there is a good deal of unwanted ambient sound�it delivers those signals originating directly in front of the mic capsule itself while rejecting those that originate from behind. The polar pattern also determines how prone a particular mic is to inducing feedback. Feedback is that characteristic nasty howling sound that occurs when a mic is placed too close to a loudspeaker�the signal from the loudspeaker is fed into the mic, then into the loudspeaker, then into the mic, over and over again until an oscillating tone is generated. Because the cardioid pattern utilized by the QTOM is so good at rejecting signal not coming from directly in front of the mic, you�ll find that use of the QTOM greatly minimizes feedback problems.
