Crown Audio 133472-1A manual Bca

Chapter 3: Glossary of Terms 27

Chapter 3

Glossary of Terms

In This Chapter

• Glossary of Terms

This section provides a handy glossary of terms used in the discussion of profes- sional audio amplifi ers. Some terms are unique to Crown amplifi ers. Most of the

terms provided do not directly relate to amplifi ers, but as amplifi ers are but one piece of a larger audio system, are often used when discussing amp usage.

English

Amperage

A measure of electrical current fl ow, also called “amps” for short. It literally equates to the number of electrons in a conductor fl owing past a certain point in a given amount of time. Ohms law defi nes current (I) as voltage (V) divided by resistance (R) with the following expression: I=V/R.

Amplifier (Amp)

A device that increases signal. Many types of amplifi ers are used in audio systems. Amplifi ers typically increase voltage, current, or both.

Amplifier Class

Audio power amplifi ers are classifi ed primarily by the design of the output stage. Classifi cation is based on the amount of time the output devices are made to operate during each cycle of swing. Amplifi ers are also defi ned in terms of output bias current (the amount of current fl owing in the output devices with no signal present). Common amplifi er classes used in professional audio amplifi ers include AB, AB+B, D, G and H.

Attenuation

A decrease in the level of a signal is referred to as attenua- tion. In some cases this is unintentional, as in the attenuation caused by using wire for signal transmission. Attenuators (circuits which attenuate a signal) may also be used to lower the level of a signal in an audio system to prevent overload and distortion.

Balanced Line

A cable with two conductors surrounded by a shield, in which each conductor is at equal impedance to ground. With respect to ground, the conductors are at equal potential but opposite polarity; the signal fl ows through both conductors.

Band-Pass Filter

In a crossover, a fi lter that passes a band or range of frequen- cies but sharply attenuates or rejects frequencies outside the band.

Barrier Block/Barrier Strip

A series of connections, usually screw terminals, arranged in a line to permanently connect multiple audio lines to such devices as recording equipment, mixers, or outboard gear. Also called terminal strip.

BCA®

BCA (Balanced Current Amplifi er) is Crown’s patented PWM (Pulse-Width Modulation) amplifi er output stage topology. Also referred to as “class-I,” Crown’s BCA “switching” technol- ogy provides for high output, exceptional reliability and nearly twice the effi ciency of typical amplifi er designs. To learn more about BCA, download and read the BCA white paper at www. crownaudio.com.

Binding Post (5-Way, Banana)

A type of electrical terminal, a binding post is most commonly found as the output connector on a power amplifi er, or as the connectors on a speaker cabinet. A binding post can accept banana plugs, spade lugs, bare wire and others. Generally, binding posts are color coded, with the black connection going to ground, and the red connecting to hot.

Bridge-Mono

An operating mode of an amplifi er that allows a single input to feed two combined output channels in order to provide a single output with twice the voltage of an individual channel in Stereo or Dual mode.

Amplifier Application Guide