1. The World Of Audio

Question 1

Analog

Answer 1

When sound is captured as an electrical signal whose levels vary in direct relationship to the original current or acoustic signal.

Question 2

Digital

Answer 2

When a signal is reduced and encoded into discrete bits of information that establish a mathematical model of the signal.

Question 3

Audio Chain

Answer 3

The series of connected audio devices used for recording or PA (public address).

Question 4

Audio Interface

Answer 4

A device that has numerous audio inputs and outputs.

Question 5

Mixer

Answer 5

An audio interface that allows several audio sources to be combined, with independent control of each signal’s loudness, tone, and stereo position.

Question 6

PA

Answer 6

Short for “Public Address System.” The primary sound system of a venue or auditorium.

Question 7

DAW (Digital Audio Workstation)

Answer 7

A computer-based recording and editing machine used for manipulating sounds. Your keyboard may double as a DAW.

Question 8

Stage Box

Answer 8

A box with multiple audio inputs and outputs at the end of a multi-core sound cable. Multi-core cables are often referred to as “snakes.”

Question 9

Wedges

Answer 9

Speakers, in the shape of a wedge, designed to sit on the floor, directed towards the performer(s).

Question 10

Fills

Answer 10

Speakers additional to the main PA or main monitors to improve the sound in particular locations. (E.g. ‘front fills’ add sound at the front of the auditorium which might be just out of range of the main PA above the stage.)

Question 11

Bass

Answer 11

The lower range of audible frequencies (below 200 to 250 Hz).

Question 12

Treble

Answer 12

The upper range of audible frequencies (above 4 kHz).

Question 13

Subwoofer

Answer 13

A speaker designed to reproduce sub-bass frequencies. A true subwoofer should be able to at least reach into the bottom octave (20-40 Hz). There are many “subwoofers” on the market that would be more accurately termed “woofers.”

Question 14

Woofer

Answer 14

A speaker that produces only frequencies below a certain range, usually below 800 Hz.

Question 15

Midrange

Answer 15

A speaker used to reproduce the middle range of frequencies. A midrange is combined with a woofer for low frequencies and a tweeter for high frequencies to form a complete, full-range system.

Question 16

Tweeter

Answer 16

A speaker that reproduces only frequencies above a certain range, usually above 3 kHz.

Question 17

XLR

Answer 17

A widely used connector for audio cables with three (or more) pins plus an outer shell that shields these pins and locks them into place. XLR is a balanced cable (see deck 5).

Question 18

1/4” (Phone Plug)

Answer 18

A widely used connector for audio cables that can be either balanced or unbalanced, depending on the number of contact points in it’s sleeve. Unbalanced 1/4” TS (tip, sleeve) have two contact points, one for transferring audio and one for use as a ground. Balanced 1/4” TRS (tip, ring, sleeve), have three contact points, one for ground, and two for transferring audio. This allows for a noise free cable.

Question 19

Jack

Answer 19

The general name for a connector at the end of an audio cable.

Question 20

Patch Cable

Answer 20

A short cable used to connect two components of an audio chain. Patching is the process of setting up your audio chain, whether you use patch cables to connect two hardware devices, or make virtual connections in computer software.

Question 21

Sound

Answer 21

Mechanical energy that is transmitted by longitudinal waves in a material medium (such as air) and is also the objective cause of hearing (Websters, edited).

Question 22

Wavelength

Answer 22

The physical distance between the start and end of one cycle of a sound wave.

Question 23

Amplitude

Answer 23

The strength or level of a sound wave or audio signal, measured in decibels (dB). Amplitude is a measurement of changes in pressure and, in acoustics, is referred to as sound pressure level (SPL).

Question 24

Sound Pressure Level (SPL)

Answer 24

The strength or level of a sound wave in air or another medium, measured in decibels (dB). (See amplitude.)

Question 25

Frequency (Hz)

Answer 25

The number of times a signal vibrates each second. Expressed as cycles per second (cps) or Hertz (Hz). The higher the frequency the higher the pitch.

Question 26

Amplifier (Amp)

Answer 26

1. An electronic device that amplifies (boosts) a low voltage, low current signal from a CD player, mixer, etc. into a higher current signal suitable for driving speakers. 2. A combination speaker/amplifier used with instruments or microphones (e.g. a guitar amp or keyboard amp).
   * As a general rule, each speaker in a sound system requires a separate amplifier. Most amplifier boxes contain two amplifiers (one for each stereo component (left and right) of the sound signal), so with a single amplifier box, you can usually drive two speakers.*