Sound Principles VCC West Philly Sound Team Training

Frequency 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

Amplitude 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 System

Input Sources Microphones Types – dynamic, condenser Patterns – omnidirectional, cardioid, supercardioid Instruments Guitar, piano, bass, drums Other CD player, iPod, computer omnidirectional cardioid supercardioid

Mixing Console Mixes, tunes, and controls the destination and volume of audio signals Combines input signals to form outputs for main and monitor speakers

Power Amplifier Take signals and amplify them so they can drive speakers Power of an amplifier is measured in Watts Make sure that the amplifier matches the impedance of the speakers being used Watch for clipping or distortion Clipping

Speakers Main Speakers Provide sound for audience Monitor Speakers Provide sound for musicians on stage Speakers are rated in terms of impedance. Common values are 2 Ohms, 4 Ohms, and 8 Ohms

Cables and Connectors Connect all the different components of the sound system Types of Cables Unbalanced – Short cables connecting instruments to amps/snake Balanced – Longer cables carrying line-level signals to and from mixer Unshielded – Thicker cables carrying amplified signals from amp to speakers XLR 1/8” (mini-plug) 1/4” RCA