This column aims to give musos, creative types, DJs Techno and Rave producers and such like minded people, enough info so that when the sound engineer or PA operators ask…" What levels ya output, do ya need a DI, what sort of connectors ya got, got all your adapters, waddaya want in foldback etc etc?" they won't be completely stuffed by all this techno-babble!! There are many things to consider, like the various signal levels, inputs & outputs, connectors…etc, etc. and the list goes on! It won't replace lots of hands on experience, but at least by learning some of the jargon you'll know the basics and not sound like a complete beginner!!

A-B TEST : Comparing the performance of two or more models of equipment such as amplifiers or speaker systems by listening and switching quickly from one to the other.

ADIABATIC : Literally, it means "not to pass through." In describing the high-density foam used inside the speakers, it means that internal reflections within the cabinet are absorbed by the foam. In physical terms, it means the mechanical energy of the sound wave is converted into heat energy.

ABSORPTION : The frequency dependent ability of a room to take up or absorb the acoustic energy radiated within it. Certain materials such as acoustical tiles / ceilings that may absorb more high frequencies than lows. Loose wall panels or cavities behind the panels may create Diaphragmatic absorptions that cause certain low frequencies to be absorbed.

AC MAINS : What you plug your power cord into, doh! US and Canadian Models 120V AC, Europe / General Model 220-240V AC, 50-60 Hz.

ACOUSTIC : The act or sense of hearing, the science of sound, or the sound heard.

ACTIVE : A type of electronic circuitry that can increase the gain or amplitude of a signal. (They can 'boost' as well as 'cut.') Active circuits need power to operate as they contain transistors, ICs, tubes or other devices.

ADSR : The 'envelope' of sound from start to finish, with Attack, Sustain, Decay and Release as parameters. [See Attack, Sustain, Decay and Release for more details.]

AFL : After Fade listen; used within mixing desks to allow specific signals to be monitored at the level set by their fader. Aux sends are generally monitored AFL rather than PFL.  [See PFL for more details.]

ALGORITHM : A computer program designed to perform a specific task, usually to create an effect or combination of effects.

AMBIENCE : The result of sound reflections in a confined space being added to the original sound giving the sound a sense of space. Ambience may also be created electronically by reverb units. The main difference between ambience and reverberation is that ambience doesn't have the characteristic long delay time of reverberation.

AMPERE : A unit of measurement of electrical current (The symbol for current is 'I'). Named after French scientist Andre Ampere (1775-1836).

AMPLIFIER : A device capable of increasing the gain (magnitude) or power level of a voltage or current that is varying with time (frequency), without distorting the wave form of the signal. The amplifier is, just as the word implies, a signal amplifier. The incoming signal from any program material source is far too weak to power a speaker system. The role of the amplifier is to take that weak signal and strengthen it to the necessary power level to operate the loudspeakers with minimal distortion.

ANALOGUE : Circuitry that uses a continually changing voltage or current to represent a signal. The origin of the term is that the electrical signal can be thought of as being 'analogous' to the original signal, i.e., the voltage that the microphone produces is the electrical analogue of the acoustic sound source.

ANECHOIC : Literally means 'no echoes' and refers to a room in which all surfaces are lined with acoustic absorption material to such an extent that the room absorbs sound energy instead of reflecting it around the room. A room that offers nearly total absorption is called an Anechoic Chamber and must be quite large in order to accommodate low frequencies.

ASSIGN : In sound mixers, assign means to switch or route a signal to a particular signal path, buss or combination of signal paths.

ATTACK : The time taken for a sound to achieve maximum amplitude. Drums have a fast attack, whereas bowed strings have a slow attack. In compressors and gates, the attack time equates to how quickly the processor can react to the incoming signal and change its gain.

ATTENUATE : To make lower in level, reduce or make quieter.

AUDIO CHAIN :The order of sequence for connecting the audio components that in total make a 'system.'

e.g.  microphone to pre-amp (mixer) to graphic equalisers to the crossovers to the amplifiers and speakers.

AUDIO RANGE : The range of frequencies that humans can hear - 20 Hz to 20,000 Hz. (Twenty cycles per second to twenty thousand cycles per second). This frequency range decreases with age and exposure to loud sounds.

AUX : Auxiliary; a control on a mixing desk designed to route a proportion of the channel signal to the effects or cue mix outputs, e.g. Aux Send.

AUX INPUT : An auxiliary input that serves as a straight connection to a signal BUS (e.g. Monitor Aux input is an Aux input to the monitor BUS.)

AUX RETURN : Line Level inputs with limited EQ, used to add or 'return' the effects to the mix.

AUX SEND : Physical output from a mixer Aux Send buss.