Bogen Microphones Innovative Solutions for Demanding Applications, Sensitivity Patterns

High-Quality Microphones

Innovative Solutions for

Demanding Applications

Bogen’s selection of high-quality, portable microphones offer clear, natural, intelligible sound. Engineered for accurate sound reproduction, each microphone is ruggedly constructed to with- stand the demands of sound installations. A variety of types and styles are available including gooseneck, desktop, handheld, wireless handheld/lavaliere, overhead hanging, and surface- mount microphones. Both contemporary and traditional designs provide accurate response and dependable perform- ance, with optimum clarity.

Sensitivity Patterns

Microphones pick up sound differently, based on the type of sensitivity pattern. There are two main types of microphones or patterns: Cardioid and Omni-Directional.

Cardioid (Uni-Directional)

This pickup pattern is sensitive to sound coming from one direction - in front of the microphone - thus, it best serves a single user. It is preferred for applications where there is like- lihood of feedback, where the ambient noise is too high or variable for a good clear signal, or where the user will be close to the microphone. Microphones with a cardioid pickup pat- tern greatly reduce the chance of reproducing unwanted sources of noise that are at the back or sides of the micro- phone, such as with an audience.

Bogen’s microphone models are crafted with professional- grade features, including models with rubberized grips, dent- proof screens, and quiet on/off glide switches. In addition, Bogen’s handheld mics feel good in the hand and reduce reso- nance from taps and handling.

A variety of accessories are available for Bogen’s line of micro- phones - including stands, mounting clips, and cables.

		0˚	330˚	0˚
	330˚	30˚		30˚
	300˚	60˚	300˚	60˚
Cardioid				Omni-
	270˚	90˚	270˚	90˚
				Directional
	240˚	120˚	240˚	120˚
	210˚	150˚	210˚	150˚
		180˚		180˚

Omni-Directional

This microphone pickup pattern is sensitive to sound from all directions - in front, back, and on the sides of the micro- phone - thus, best serving a group of users. Omni-direction- al microphones are preferred for use in studios, offices, round-table discussions, or other environments where there is no ambient background noise (such as a conference room). Microphones with an omni-directional pickup pattern provide a smoother response than microphones with a car- dioid pickup pattern.

Dynamic vs. Electret Condenser

Microphones are transducers, or energy converters, which sense acoustic energy (sound waves) and convert them into electrical energy signals. There are two common methods for microphones to do this: 1) the electromagnetic technique used in dynamic type microphones, and 2) the electrostatic tech- nique used in electret condenser type microphones.

Dynamic

Dynamic microphones consist of a coil of wire attached to a diaphragm that sits in a magnetic field that is created by a small magnet. When sound waves cause the diaphragm to vibrate, the motion of the coil within the magnetic field creates electrical signals that can be amplified or recorded.

These types of microphones produce a smooth, extended response, and provide good linearity. Their output level is high enough to work directly with most microphone inputs and have an excellent signal-to-noise ratio. They are rugged, reliable, and do not require batteries or external power supplies to operate.

Electret Condensers

Electret condenser microphones use a lightweight, permanently- polarized membrane and a fixed plate to create a capacitor. Sound waves cause the membrane to vibrate, which changes the distance between the membrane and fixed plate causing a change in capacitance. Using a built-in electronic pre-amplifier circuit, the capacitance fluctuations are converted to electrical signals that can be amplified or recorded. Because of the built-in pre-amplifier, power must be supplied to the microphone exter- nally. For convenience, the same shielded 2-conductor cable that carries the audio from the microphone is used to supply the DC voltage to the microphone’s pre-amp circuit. This method of sup- plying power to the microphone is called “Phantom Power”.

Electret condenser microphones respond quickly, have excellent linearity, and are very sensitive. They respond with clarity to transient sounds, provide a very uniform frequency response, and have an outstanding low-frequency pickup.