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  • Cone

    (speaker) A light material forced into motion representative of sound waves, causing changes in air pressure analogous to those sound waves.

    Crystal microphones

    Transducers of mechanical energy into electrical energy by the use of crystal salts or ceramics (piezoelectric material) that, when their shape is distorted by changes in air pressure on a diaphragm, produce minute voltages.

    Dynamic Microphones

    Transducers using a coil of wire moving through a magnetic field to transduce mechanical energy into electrical energy.

    Condenser Microphones

    Transducers of mechanical energy that create voltage fluctuations by varying the relative positions to each other of two conductors that have been polarized using an electric current.

    Phantom Power

    Places electrons on one side of a capacitor attached to the diaphragm of a condenser microphone. The action of the diaphragm forces some of those electrons to cross from one side to the other of the capacitor, dependent on the force of the diaphragm's movement.


    A passive device that stores a small electric charge.


    These devices carry a permanent static electric charge.


    Multiple wires, each insulated from the other, that run in tandem with each other. The wires twist around each other to help cancel noise.

    Shielded cable

    has a network of wire mesh that runs eventually into the earth, surrounding the wires, thus preventing any influence from electrical disturbances in the environment.

    Polar Pattern

    The shape of the area in space to which a microphone is sensitive.


    The signal entering an electronic component.


    The signal leaving an electronic component.


    A crystalline material (usually made of germanium). It is a non-linear amplifying element used in almost all audio circuitry today. Great effort must be made to reduce distortion introduced by these devices in order to make their output linear, or like the original signal, only louder.


    The amount of increase of current allowed to flow through a circuit. Incorrectly called "volume," since that is a sensory judgement made about sounds and has little, if anything, to do with an electronic circuit.

    speaker unit

    The combination of two or more individual tweeters, midrange speakers or woofers in a single speaker enclosure, with the proper crossover networks.

    speaker system

    The combination of two or more speaker units in an audio sound system to reproduce the original sound picture.

    cross-over networks

    Essentially, electronic routing systems sensitive to different frequency ranges.

    bass reflex speaker

    refers to the kind of cabinet that any kind of speaker is mounted in. A speaker is mounted in the front of a box. Vent holes are also placed on the front to allow reflected and reinforced sounds from inside the box to combine with those emanating directly from the front of the speaker.

    Air Suspension Speaker

    Refers to the cabinet in which a speaker is mounted. An airtight, sealed box, that is responsible for returning the speaker cone to its neutral position using the air pressure contained within the cabinet. These are sometimes called "acoustic suspension speakers."

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