Cardioid: A microphone that picks up sound in a heart-shaped and directional pickup pattern that is most sensitive to sounds coming from the front and sides while rejecting sounds coming from the rear.

Condenser Microphone: A high-quality mic whose transducer consists of a diaphragm, backplate and capacitor. A condenser microphone picks up sounds via an electrically charged, metal diaphragm, which is separated from a conductive back plate by a thin air layer. Sound waves striking the diaphragm cause a minuscule voltage change, which is increased by a tiny amplifier circuit within the mic body.

Dynamic Microphone: A rugged microphone whose transducer consists of a diaphragm connected to a moveable coil. Dynamic microphone: a transducer that relies on the law of induction, with an output proportional to the velocity of a moving element within a magnetic field.

Omnidirectional Microphone: A microphone that picks up sound from all directions.

Lavalier Microphone: or lavalier is a small microphone that can be worn attached with small clips to collars, ties, or other clothing in order to allow hands-free operation during public speaking. Also referred to as a Lapel or Lav microphone.

Wireless Microphone: as the name implies, it is a microphone without a physical cable connecting it directly to the sound recording or amplifying equipment with which it is associated. A microphone with a self-contained, built-in miniature FM transmitter that can send the audio signal several hundred feet, thereby eliminating the need for cables running between the microphone and the recorder or amplifier. Both standard and lavalier microphones come in wireless.

Handheld Microphone: A microphone that a person holds to speak or sing into.

Podium Microphone: Microphone available to a speaker at the podium.

Audience Microphone: Microphone(s) available to members of the auduience to ask questions.

Desktop or Panel Microphone: Placed on a desk or table in front of speaker(s)

Shotgun Microphone: A highly-directional microphone used for picking up sounds from a distance.

Straight Stand: A mic stand that is adjustable in height but has no other adjustments. The microphone mounts directly on top of the stand. Straight stands can have heavy metal round bases or folding tripod bases.

Boom Stand: The addition of boom arm to the top of a straight stand makes the mic stand a "boom stand". The microphone mounts at the end of the boom, allowing more flexibility in mic placement.

Desk Stand: A short version of a "straight stand" designed to sit on a desk or table top, rather than on the floor.

Goose Neck: A flexible metal arm that mounts on the end of a mic stand (straight or desk) to give additional flexibility in mic placement. The microphone is mounted on the end of the goose neck.

Audio Mixer: The piece of equipment used to gather, mix and amplify sounds from multiple microphones and then send the signal on to its destination. Common brands include Yamaha, Mackie, Alexis.

Input Channel: On an audio board, the control into which a microphone, tape recorder or other source is plugged.

Fader: The audio volume control that is designated for a particular input channel.

Master fader: The audio volume control that's located after all the input channel controls and after the submaster controls.

Group Master Fader: A volume control on an audio board that handles a subgroup of input channels before they are sent to the master fader.

Amplifier: A device which electronically magnifies an audio signal for distribution and/or transducing purposes.

Preamp: An electronic device that magnifies the low signal output of microphones and other transducers before the signal is sent to a mixing board or to other amplifiers.

Equalization: Emphasizes, lessens or eliminates certain audio frequencies.

Reverberation: The reflection of a sound a sufficient number of times that it becomes non-directional and persists for some time after the source has stopped. The amount of reverberation depends on the relative amount of sound reflection and absorption in the room.

Compression-Limiting: In simple terms, a compressor is an automatic volume control. Loud sounds over a certain threshold are reduced in level while quiet sounds remain untreated.

Delay: In audio reinforcement, a straight delay is used to compensate for the passage of sound through the air. The delayed signal alone is sent to loudspeakers so that the speakers reinforce the stage sound at the same time or slightly later than the acoustic sound from the stage.

Passive: Speaker or cabinet which requires external amplifier to produce sound.

Active: Speaker or cabinet in which amplifier is built in elimitaing the need for external amplification.

Line Array Systems: A column of vertically arranged loudspeakers, usually hung from trussing or structural steel, that is capable of long and very focused throw distances. Line array columns are generally curved to provide precision coverage for larger audiences.

Amperage: A measure of the amount of current flowing in an electric circuit. Devices such as cables and dimmers are rated in terms of their maximum capacity in amps. Devices such as lamps or motors that consume electrical energy rated in terms of amperage required for proper operation. Any technician working with electrical equipment must understand how to properly connect equipment to not create an overload situation. Standard 12/3 stage cable is rated for 20 amps maximum. Amperage=Wattage/Voltage.

Voltage: The electric potential which exists between two components in an electrical system. Lamps are rated in terms of wattage at a specific voltage. Operating a lamp at another voltage from that which it is rated may cause the lamp to burn at less than full intensity or to burn out very quickly.

Wattage: The measurement of the amount of power used by an electrical device. Lamps are rated in terms of wattage. Dimmers are rated in terms of their maximum load capacity in wattage. Wattage=Amperage*Voltage.

Kilowatt: 1000 watts.

Truss: A steel or aluminum structure used for rigging stage lighting instruments, scenery, or other equipment for temporary use.

Box Truss: An aluminum or steel support structure often used for temporary rigging of lights, scenery, or sound equipment. As the name suggests a box truss is rectangular in shape creating a rigid structure which is easy to stack and load onto a truck. An additional advantage of box truss over other truss shapes is the ability to hang lighting instruments inside the truss, where they can remain protected while in transport.

Triangle Truss: A triangular shaped truss such as that used for radio towers. Triangle truss has the disadvantage over box truss that instrumentation must be struck from the truss before it can be loaded into a truck.

Pre-hung Truss: A truss or truss section which has been pre-assembled with lighting equipment and connecting devices in the shop prior to installation at load-in. Using a pre-hung truss saves many hours when loading a show in or out, and makes for an efficient method of storing equipment on a truck.

Rigging: The process by which scenery, truss, or other equipment is flown on aircraft cable or chain.

Rigger: A technician chiefly responsible for the rigging for a tour or production.

Hanging Point: The point where rigging is attached to a truss or piece of scenery. Location of hanging points must be determined for structural safety, but must be reconciled with available pickup points in the building or structure to which the truss is being rigged.

Pickup Point: (Pick Point) An architectural or structural point to which scenery or trussing can be rigged for flying purposes. Available pickup points in a particular venue must be reconciled with necessary hanging points on the equipment to be lifted.

Span Set: A loop of nylon webbing wrapped around load bearing structures at the points to which it will be rigged.