Live+Sound

PA: -stands for public audio -EQ -mixer -mic -stands -power -XLR

EQ is the color and timbre of the sound but it is also used for reducing feedback

Reverb gives you the sense that you have space, a really fast echo

A Cross Over splits the audio signal into two parts---high frequencies and low frequencies--and sends them to two different speakers

A amplifier boosts (amplifies) audio signal

Speakers convert signal so sound waves (mains send sound to audience, monitors send sound to performers) subwoofer takes signal from Cross over low frequency output to boost all low frequencies through a special speaker

never want power cables and mic cables next to each other

Trim is top knob on mixer...tells how much signal mixer is excepting from the input device

PFL (stands for pre fader level) button at bottom shows meter on side (as long as not in red, it is good....get just below red)

low cut button cuts out lows so you can crank mic without feedback

Aux can do send and returns, can send signal to just monitors,

When setting up PA system, last device to turn on is always the amplifier....when done, turn off amp first, then everything else

Keeps noise from going into the system:

1. Keep your mic cables perpendicular to power cables, if not away from them 2. Keep everything plugged into the same circuit/spot 3. Ground lift 4. Electromagnetic interference 5. Direct box 6. Use balenced cables whenever possible 7. Use short cables whenever possible 8. Don't buy cheap radio shack cables 9. Drop gain on amp, let mixer do the work (raise on mixer) 10. EQ (last resort)

Any instrument needs to have a level check

Determining period: t=1 m/s

LOOK UP FOR TEST!!!!!: Determining wavelength: A=c/f.

Determining Frequency: F=565/d

LOOK UP FOR TEST!!!!!:

1. Room Reflections (comb filtering)

Bass frequencies are generally those from 20Hz up to 200Hz

Comb filtering occrs when sound source or recording source is near a reflective boundry....solution is aborption

2. Slap Echo

3. Standing waves Axial room resonace modes....length axis, hight axis, width axis....types of modes: axial (worst), tangental, oblique Room graph: