Headworn Microphones

Speech
Common to all auditoria, churches, rooms for education, conference rooms, courtrooms, or theaters, is that one or more people address an audience. Sometimes the speakers are not trained; they have not learned to speak up in a clear and well-articulated way. Moreover you cannot be sure that the speaker has learned to use a microphone. The immediate solution is to gain the signal in order to obtain adequate amplification. This may cause excessive sensitivity to acoustical feedback. A good solution to a problem like this is to use a microphone that is worn by the speaker.

A microphone mounted on a headband used in connection with a wireless system provides a number of advantages. First of all the microphone is always close to the sound source. As a consequence, the microphone does not need to be gained as much. This is especially an advantage if several microphones are used simultaneously. Furthermore, it is a great advantage that the speaker has total freedom of movement. The speaker is not chained to the pulpit, the teacher can move freely in front of screens, or black-/whiteboards.

Directional characteristics
When you have decided on a headband microphone, the next step is to pick the right directional characteristic. DPA Microphones offers three headband versions: 4065 and 4066 are both omnidirectional, 4088 is a cardioid. All three have special advantages.

The DPA 4065 and 4066 have omnidirectional characteristics, hence the microphone is sensitive to sound from all directions. Furthermore, the timbre of the sound remains constant regardless of the distance between the sound source and the microphone. The positioning of microphones with omnidirectional characteristics is not a critical issue. Normally, a microphone with an omnidirectional characteristic will be chosen if the speaker is not accustomed to positioning a microphone on his head. An omni microphone is generally not very sensitive to wind, breathing and handling noises.

The DPA 4088 has a cardioid-shaped directional characteristic. When pointed toward the mouth the sensitivity to sounds coming from the rear is very low. All microphones with a (cardioid) directional pick-up pattern have a special quality, namely the raising of low frequency content whenever the microphone is close to the sound source (proximity effect). This is exactly what happens with the typical placement of a DPA 4088, which is just a few centimeters from the corner of the mouth. In order to get a flat response a correction is introduced, and you get both a natural sounding voice and level reduction of distant sound sources, especially at low frequencies.

A headband microphone with cardioid characteristics is therefore very convenient when the user is in the middle of noisy surroundings or in situations where high gain is needed.

As the microphone can be sensitive to breath if placed incorrectly, it is important that the microphone is always placed according to the instructions given in the manual.

A headband microphone consists of a neck brace with two ear hangers and a microphone boom. Both the brace and boom can be adjusted for optimum fit and comfort.

Singing
When the microphone is to be used by a performing singer on stage, typically there are a lot of sounds radiated from musical instruments, from monitor speakers, etc. Normally a minimum of this background sound is wanted. However, at the same time the singer's voice should sound as nice as possible.

This is why the DPA 4088 is an excellent first choice in this situation. Due to the design as a cardioid microphone there will in general, compared to an omni, appear only half the amount of the background sounds. Furthermore the low-frequency sounds from loudspeakers, drums, etc., will be reduced to 1/10 or less.