Music Technology

Chapter 2

Bit Depth

amount of binary digits that can be used to represent the data being recorded

Bit

an amount of binary digits

Compression

reducing a file size by sacrificing some of the audio quality

Samples

numerical values/ a series of digits converted from discrete signals

Sampling Rate

how many discrete signals an audio signal can be broken down into

Audio Interface

converts audio signals into a digital format

A to D (“analog to digital”)

a sound is captured by a mic (analog) and converted into a signal (digital)

Feedback

a piercing sound caused by mics being close to speakers, especially when sound levels are high. The speaker amplifies its own signal

Stems

another word for tracks

unity gain “U”

level of gain where no volume is being added or taken away

-inf

negative infinity decibels, meaning "no sounds”

Stage Monitor

a speaker on stage for the performers that comes from the mixers AUX outpu

What is the problem with a signal being too weak?

it is difficult to use the mixer’s features for that channel

Clip

occurs when a signal is too strong, resulting in an unpleasant and undesired distortion

Pad button

decreases gain by a set amount

Boost button

increase gain by a set amount

Gain

the amount of boost and cut applied to the incoming signal

Boost

strengthen

Cut

weaken

Mixing Board

used to create a balanced mix of different audio signals, and then send that mix back out

Unbalanced signal

signal that are susceptible to noise and interference, like guitars and basses

Balanced signal

when a signal (hot) is inverted (cold) to eliminate unwanted hum and noise, like microphones

XLR Cable

a balanced, three prong cable that has a ground, hot (+), and cold (-) signal used for Lo-Z instruments and DIs

Thru Output

a part of the DI that allows the input signal to be sent to other Hi-Z inputs (like a stage guitar amplifier)

Direct Box/DI

a device that takes a Hi-Z level to a Lo-Z level (typically for a mixing board)

distortion

a very low signal caused by a mismatch in impedance type

Lo-Z

low impedance (weaker than line level) like a microphone

Hi-Z

high impedance (weakest of signals) like guitars

Line Level

the strongest signal, like a synthesizer

Input

when a signal reaches a device

Output

when a signal leaves a device

RCA connections/cable

white and red is for audio; white, red, and yellow is for video; sometimes used for stereo

Channels

another word for audio signals

Stereo

two-channel signals simultaneously sent, one for the left and one for the right

1/8” TRS Cable

sends two different audio signals through headphone jacks

Audio Snake

a bundle of cables wrapped together to route audio from one location to another

Preamp

a device that adds strength to a signal

1/4” TS cable

a shielded instrument cable that sends out unbalanced signals for Hi-Z instruments (like electric guitars and basses)

1/4” TRS cable

an instrument cable that sends out balanced signals for headphones, boom mics, and stereo recordings. Can be used as stereo and gives phantom power

Signal Path

the way a signal travels to and through audio devices and cords

IEC cable

a power cable mainly used for speakers and amps

Pick-up

a transducer used for electric guitars that converts the acoustic sound into an electrical signals by either magnets or crystals

Dynamic Microphones

a less sensitive mic best placed close to a sound to prevent sound bleeding

Condenser microphones

a much more sensitive mic that should be placed some distance away from a sound source. These require 48V (or phantom power) to operate.

Crossover

the part of an amplifier that filters the low frequency content below a certain specified number (Hz) and sends it to a subwoofer

Types of ways that microphones can pick up sound

Omnidirectional, Figure 8, Cardioid, and Unidirectional

Band

a designated frequency range within a spectrum; a certain group of frequencies

Digital audio workstation (DAW)

a software program that uses recording, editing, and playback

Gain stage

the part of a mixer where a signal is weakened or strengthened

lossy and lossless compression

when parts of a file are cut out to save space and quality, like MP3 files, vs when they aren’t, like a zip file

Panning

when an audio signal is adjusted to be stronger in a certain speaker

Mono

when the same audio content comes out of multiple speakers