Sound PrinciplesSound Principles

VCC West Philly Sound TeamVCC West Philly Sound Team

TrainingTraining

FrequencyFrequency

•Frequency determines the pitch of a sound

•Higher frequencies make higher notes

•Frequency is measured in Hertz (Hz) or cycles per second

Common Frequency Bands:

•Low: 20 Hz – 250 Hz center: 100 Hz

•Mid: 250 Hz – 5 kHz center: 1 kHz

•High: 5 kHz – 20 kHz center: 10 kHz

AmplitudeAmplitude•Amplitude determines the volume or intensity of a sound wave

•Sound intensity is measured in decibels (dB)

•dB is a measurement relative to a reference sound level

•A 10 dB sound is 10 times the intensity of the reference level

•A 20 dB sound is 100 times the intensity of the reference level

•A 30 dB sound is 1000 times the intensity of the reference level

•A 0 dB sound has the same intensity as the reference level

Basic Sound SystemBasic Sound System

Input SourcesInput Sources

MicrophonesMicrophones

Types – dynamic, condenserTypes – dynamic, condenser

Patterns – omnidirectional, Patterns – omnidirectional, cardioid, supercardioidcardioid, supercardioid

InstrumentsInstruments

Guitar, piano, bass, drumsGuitar, piano, bass, drums

OtherOther

CD player, iPod, computerCD player, iPod, computer

omnidirectional cardioid supercardioid

Mixing ConsoleMixing Console

Mixes, tunes, and controls the Mixes, tunes, and controls the destination and volume of audio destination and volume of audio signalssignals

Combines input signals to form Combines input signals to form outputs for main and monitor outputs for main and monitor speakersspeakers

Power AmplifierPower Amplifier

Take signals and amplify them so Take signals and amplify them so they can drive speakersthey can drive speakers

Power of an amplifier is measured Power of an amplifier is measured in Wattsin Watts

Make sure that the amplifier Make sure that the amplifier matches the impedance of the matches the impedance of the speakers being usedspeakers being used

Watch for clipping or distortionWatch for clipping or distortion

Clipping

SpeakersSpeakers

Main SpeakersMain Speakers

Provide sound for audienceProvide sound for audience

Monitor SpeakersMonitor Speakers

Provide sound for musicians on Provide sound for musicians on stagestage

Speakers are rated in terms of Speakers are rated in terms of impedance. Common values are impedance. Common values are 2 Ohms, 4 Ohms, and 8 Ohms2 Ohms, 4 Ohms, and 8 Ohms

Cables and ConnectorsCables and Connectors

Connect all the different components of the sound systemConnect all the different components of the sound system

Types of CablesTypes of CablesUnbalanced – Short cables connecting instruments to amps/snakeUnbalanced – Short cables connecting instruments to amps/snakeBalanced – Longer cables carrying line-level signals to and from mixerBalanced – Longer cables carrying line-level signals to and from mixerUnshielded – Thicker cables carrying amplified signals from amp to Unshielded – Thicker cables carrying amplified signals from amp to speakersspeakers

XLR 1/8” (mini-plug)1/4” RCA