Technical Terminology
| Term | Definition | Daily Use | Category |
|---|---|---|---|
| AC | Alternating Current. The type of electrical current that runs through houses and buildings to power electrical devices/equipment. Example: Electrical extension cables. | Yes | Sound or Audio; Lighting or electrics |
| Acoustics | Acoustics is the science of sound, including its production, transmission and effects. The acoustics of a room are those qualities that together determine its character with respect to the perception of sound. | Yes | Sound or Audio |
| Ambient Noise | Ambient noise encompasses all sound present in a given environment, being usually a composite of sounds from many sources near and far. | Yes | Sound or Audio |
| Attenuation | The reduction of sound energy as a function of distance traveled. | Yes | Sound or Audio |
| Backdrop | Yes | Rigging; Production | |
| Balanced | See also Stereo. | Yes | Sound or Audio |
| Blackout | The sudden extinguishing of all stage lights, leaving the theatre in blackness, As contrasted to a fade out which is a gradual fading of the lights. | Yes | Lighting or electrics |
| Boom Stand | Yes | Sound or Audio | |
| Boominess | Low frequency reflections. In small rooms, acoustical panels with air space behind can better help control low frequency reflectivity. | Yes | Sound or Audio |
| Buss | Yes | Sound or Audio; Lighting or electrics | |
| Buzz | See also Hum and Feedback. The only real difference between "hum" and "buzz" is that buzz has more harmonics, and those harmonics extend to a higher audible frequency. |
Yes | Sound or Audio |
| Cart | Yes | ||
| Caster | Yes | Carpentry | |
| CAT 5e, 6 | Category 5e, Category 6, etc. A data cable normally used to transmit data from the internet to computers. See also Hard line connection. | Yes | Sound, Video, Computers |
| Chorus | (1) an ensemble of characters representing the general public of the play, (2) In musical plays, an ensemble of characters who sing and/or dance independently. | Yes | Sound or Audio; Carpentry |
| Cue | Yes | Production | |
| Cycle | In acoustics, the cycle is the complete oscillation of pressure above and below the atmospheric static pressure. | Yes | Sound or Audio |
| Cycles Per Second | The number of oscillations that occur in the time frame on one second. (See Frequency). Low frequency sounds have fewer and longer oscillations. | Yes | Sound or Audio |
| Data Connection | Ethernet connection. A connection using an RJ45 (Registered Jack) connector for the purpose of connecting a computer or data-enabled device to a telecommunications system. | Yes | Computers |
| Decibel (dB) | A dimensionless unit which denotes the ratio between two quantities that are proportional to power, energy or intensity. One of these quantities is a designated reference by which all other quantities of identical units are divided. The sound pressure level in decibels is equal to 10 times the logarithm (to the base 10) of the ratio between the pressure squared divided by the reference pressure squared. The reference pressure used in acoustics is 20 microPascals. | Yes | Sound or Audio |
| Dimmer | The electrical device (technically a potentiometer) which regulates the current passing through the bulb filaments and, thereby, the amount of light emitted from the lighting instruments. | Yes | Lighting or electrics |
| Dolly | Yes | ||
| Downstage | The part of the stage closest to the audience. The term derives from the 18th century when the stage was raked so that the front part of was literally below the back (or upstage) portion. | Yes | Production |
| Dress Rehearsal | A rehearsal, perhaps one of several in full costume; usually also with full scenery, properties, lighting, sound, and technical effects. Ordinarily the last rehearsal prior to the first actual performance before an outside audience. | Yes | Production |
| Echo | Reflected sound producing a distinct repetition of the original sound. Echo in mountains is distinct by reason of travel after original signal has ceased. | Yes | Sound or Audio |
| EMS Campus | A software program by Dean & Evans, Inc. that the Kehr Union Building uses to keep track of all building events and equipment. This is the main scheduling tool for the KUB." | Yes | |
| Feedback | See also hum abd buzz. Feedback is caused by an amplified signal from a sound system re-entering a microphone, and getting constantly re-amplified (i.e. a feedback loop). It is usually high pitched. To remedy, turn down the microphone or main system volume. See Audio feedback at wikipedia.org Feedback is not caused by running an AC cable and an audio cable too close. |
Yes | Sound or Audio |
| Fly | (v.) To raise a piece of scenery (or an actor) out of sight, by a system of ropes and/or wires. | Yes | Rigging |
| FOH | "Front of House." | Yes | Sound; Production; Video |
| Frequency | The number of oscillations or cycles per unit of time. Acoustical frequency is usually expressed in units of Hertz (Hz) where one Hz is equal to one cycle per second. | Yes | Sound or Audio |
| Gel | Transparent colored sheets of material placed in front of a lighting instrument used to change the color of the light beam. | Yes | Lighting or electrics; Production |
| Gobo | No | Lighting or electrics | |
| Ground | Yes | Sound or Audio; Lighting or electrics | |
| Group | See also Subgroup. | Yes | Sound or Audio; Lighting or electrics |
| Hand Truck | Yes | ||
| Hard line connection | A connection via a cable instead of via wireless transmission. | Yes | Sound or Audio; Video; Computers |
| Hearing Impairment | A degree of hearing loss, temporary or permanent, due to many causes. Hearing loss can be caused by illness, disease, or exposure to excessively high noise levels. Affects 25 – 50 million people in USA of all ages. Hearing impairment as generally used means a hearing loss of mild, moderate or severe degree as opposed to “deafness” which is generally described as little or no residual hearing with or without the aid of an assistive listening device. Hearing impaired persons are particularly adversely affected by long reverberation times. | Yes | Sound or Audio |
| Hearing Range |
16 – 2000 Hz (Speech Intelligibility) 600 – 4800 Hz (Speech Privacy) 250 – 2500 Hz (Typical small table radio) | Yes | Sound or Audio |
| Hertz (Hz) | Frequency of sound expressed by cycles per second. (See Cycle). | Yes | Sound or Audio |
| House | Theatrical term indicating the performance venue. | Yes | Production |
| House Left | Left from the audience point of view facing the stage. | Yes | Production |
| House Right | Right from the audience point of view facing the stage. | Yes | Production |
| Hum | See also Buzz and Feedback. An unwanted low-frequency sound caused by power-line frequencies in any audio component. This hum is generated by oscillating electric currents induced in sensitive (high gain or high impedance) audio circuitry by the alternating electromagnetic fields emanating from nearby mains-powered devices like power transformers. The audible aspect of this sort of electric hum is produced by amplifiers and loudspeakers. There are three basic ways that hum and other power line-related noises can get into an audio system.
solid-state light dimmers can also cause hum. These devices work by changing the amount of time the full power line voltage is applied to the light being controlled, as opposed to actually raising and lowering the voltage. Although AC power is supplied by the power company as a pure sine wave (having no harmonics), the dimmer's sudden switching of the voltage on and off actually generates harmonics which extend to very high frequencies. And these high frequency harmonics can get into audio gear both by radiation through the air and also by traveling through the power wiring directly into the audio circuitry. |
Yes | Sound or Audio |
| IMP | Integrated Multimedia Presentation. See IMP Stations. | Yes | Sound or Audio; Video |
| Impedance | Yes | Sound or Audio | |
| Input | No | Sound or Audio; Video | |
| Lavaliere | See also lapel. | Yes | Sound or Audio |
| Mono | See also Unbalanced. | Yes | Sound or Audio |
| Noise | Unwanted sound that is annoying or interferes with listening. Not all noise needs to be excessively loud to represent an annoyance or interference. | Yes | Sound or Audio |
| Noise Reduction (NR) | The amount of noise that is reduced through the introduction of sound absorbing materials. The level (in decibels) of sound reduced on a logarithmic basis. | Yes | Sound or Audio |
| Octave | A pitch interval of 2 to 1. The tone whose frequency is twice that of the given tone. | Yes | Sound or Audio |
| Octave Bands | Sounds that contain energy over a wide range of frequencies are divided into sections called bands. A common standard division is in 10 octave bands identified by their center frequencies 31.5, 63, 250, 500, 1000, 2000, and 4000 Hz. | No | Sound or Audio |
| Output | No | Sound or Audio; Video | |
| Phantom Power | "in the context of professional audio equipment, is DC electric power transmitted through microphone cables to operate microphones that contain active electronic circuitry. It is best known as a convenient power source for condenser microphones, though many active direct boxes also use it." Wikipedia.com source. | Yes | Sound or Audio |
| Pitch | The perceived auditory sensation of sounds expressed in terms of high or low frequency stimulus of the sound. | Yes | Sound or Audio |
| PoE | "Power over Ethernet" | No | Sound or Audio; Lighting or electrics; Video |
| Preamp | Yes | Sound or Audio | |
| Props (Properties) | The furniture and objects used in productions. | No | Production; Carpentry |
| Pyro | Pyrotechnics | No | Lighting or electrics; Production |
| Receiver | Yes | Sound or Audio; Video | |
| Reflection | The amount of sound wave energy (sound) that is reflected off a surface. Hard non-porous surfaces reflect more sound that soft porous surfaces. Some sound reflection can enhance the quality of the signal of speech and music. | Yes | Sound or Audio |
| Resonance | The emphasis of sound at a particular frequency. | Yes | Sound or Audio |
| Resonant Frequency | Resonant Frequency is a frequency at which resonance exists. | Yes | Sound or Audio |
| Reverberation | Sound after it is ended at the source will continue to reflect off surfaces until the sound wave loses energy by absorption to eventually die out. | Yes | Sound or Audio |
| Reverberation Time | The reverberation time of a room is the time it takes for sound to decay by 60 dB once the source of sound has stopped. Reverberation time is the basic acoustical property of a room which depends only on its dimensions and the absorptive properties of its surfaces and contents. Reverberation has an important impact on speech intelligibility. | Yes | Sound or Audio |
| RF (Radio Frequency) | No | Sound or Audio; Lighting or electrics | |
| Rider | An object or piece of equipment positioned on top of a rolling cart or equipment case. Example: look at the wording on top of the large sound system Front of House (FOH) rack. | Yes | Sound or Audio; Lighting or electrics |
| Rigging | No | Rigging | |
| Set | Yes | Production; Carpentry | |
| Stage Direction | Scene descriptions, blocking instructions, and general directorial comments written, usually by the playwright, in the script. | No | Production |
| Stereo | See also Balanced. | Yes | Sound or Audio |
| Signal to Noise Ratio | The sound level at the listeners ear of a speaker above the background noise level. The inverse square law impacts the S/N ratio. | Yes | Sound or Audio |
| Sound | Sound is an oscillation in pressure, stress particle displacement, particle velocity in a medium. Sound produces an auditory sensation caused by the oscillation. | Yes | Sound or Audio |
| Sound Absorption | The property possessed by materials, objects and air to convert sound energy into heat. Sound waves reflected by a surface causes a loss of energy. That energy not reflected is call is absorption coefficient. | Yes | Sound or Audio |
| Sound Level | A subjective measure of sound expressed in decibels as a comparison corresponding to familiar sounds experienced in a variety of situations. | Yes | Sound or Audio |
| Snake | Yes | Sound or Audio | |
| Speech Intelligibility | The ability of a listener to hear and correctly interpret verbal messages. In a classroom with high ceilings and hard parallel surfaces such as glass and tile, speech intelligibility is a particular problem. Sound bounces off walls, ceilings and floors, distorting the teacher’s instructions and interfering with students’ ability to comprehend. Centers between 250 and 4000k. | Yes | Sound or Audio |
| Speech Privacy | The degree to which speech is unintelligible between offices. Three ratings are used: Confidential, Normal (Non Obtrusive) and Minimal. | Yes | Sound or Audio |
| Stage Left | Left from the actor’s point of view on stage facing the audience. | Yes | Production |
| Stage Right | Right from the actor’s point of view on stage facing the audience. | Yes | Production |
| Strike | To remove a set piece or from the stage ("Strike that chair.") To "strike the show" is to disassemble the entirety of the set, return all equipment to storage and leave the venue as it was before the show was set up. May be used as a noun to refer to the event at which the show is struck (wikipedia.org). |
Yes | Sound or Audio; Lighting or electrics; Rigging; Production; Video |
| Subgroup | Yes | Sound or Audio; Lighting or electrics; Video | |
| Tape, Board | Yes | Sound or Audio; Lighting or electrics | |
| Tape, Gaff | Yes | Sound or Audio; Lighting or electrics; Production | |
| Tape, Spike | Yes | Production; Carpentry | |
| Transceiver | Example: The orange device used with portable lighting. In this picture the tranceiver unit is being used as a transmitter. | Yes | Sound or Audio; Lighting or electrics; Video |
| Twofer | Pronounced "too-fer". A lighting cable in which two lighting instruments can be connected. | Yes | Lighting or electrics |
| Upstage | That part of the stage farthest from the audience; the rear of the stage. So called because it was in fact raised (“up”) in the days of the raking stage. | Yes | Production |
| Vibration | Vibration is a force which oscillates about some specified reference point. Vibration is commonly expressed in terms of frequency such as cycles per second (cps), Hertz (Hz), cycles per minute (cpm) or (rpm) and strokes per minute (spm). This is the number of oscillations which occurs in that time period. The amplitude is the magnitude or distance of travel of the force. | Yes | Sound or Audio |
| Voice Conneciton | Phone connection. Phone jack. A connection using an RJ11 (Registered Jack) connector for the purpose of connecting a telephone to a telecommunications system. | Yes | Sound or Audio |
| Volume | The cubic space of a room bounded by walls, floors, and ceilings determined by the Volume=Length x Width x Height of space. Volume influences reverberation time. | Yes | Sound or Audio |
| Wavelength | Sound that passes through air produces a wavelike motion of compression and refraction. Wavelength is the distance between two identical positions in the cycle or wave. Similar to ripples or waves produces by dropping a stone in water. Length of sound wave varies with frequency. Low frequency equals longer wavelengths. | Yes | Sound or Audio |
| Wings | The vertical pieces of scenery to the left and right of the stage, usually parallel with the footlights. | No | Production |
