Sound Systems-Getting Wired Up
All cables must be shielded. (Eliminates unwanted noise)
Cables longer than 25ft. Should be XLR balanced low impedance.
Outputs of electronic instruments unbalanced 1/4” plug should use a direct box (also known as D.I. for direct input) is a small device that balances the signal and reduces it to a microphone level.
The direct box has a high impedance, unbalanced 1/4" jack input and a low impedance, balanced XLR jact output that is fed directly to a balanced microphone input on a mixer.
RCA jacks are the standard means of connection for home stereo components, such as CD players, mp3 players and semi-pro recording equipment.
There is a significant shift in cable requirements for connecting the output of the amplifier to the speaker inputs in home theater applications.
Speaker cables are not shielded ad require a larger or heavier wire gauge to handle the power from the output from the amplifier.
Speaker cables are normally made of a two conductor cable similar to a lamp cord.
A heavy wire gauge should be used for high wattage or long speaker cable runs.
High wattage applications should be kept as short as possible.
Cable lengths over 50' can result in a loss of power and fidelity in gauges that are too light.
Sound reinforcement speaker cables range from 12 to 18 gauge.
Wire gauge is the measurement of the diameter of the copper conductor in a wire.
The thickness of the wire is measured backwards-12 gauge wire is thicker than 14-gauge.
Wire speakers to an amplifier using the positive ("+") and negative ("-") terminals. Positive to positive=Negative to negative.
If the wires of one of the speakers are reversed it will be out of phase and the stereo imaging will not be correct. Results in diminished low frequencies and sounds that are panned to the center of the stereo field will appear to come from the two sides rather than the center.
Some speaker cables in small live sound applications (such as a coffee house) will generally use a 1/4" cable connector.
Larger systems use specially designed speaker cables for connecting the speaker from the power amplifier.
Choose Your Mixer-Powered/Unpowered.
Pick out mics that fit your situation.
Choose appropriate PA speakers-Active/Passive.
Pick out the right monitor system.
Get the right power amplification.
Add signal processing/effects.
Cable up/connect your rig.
Rack up and pack up your equipment.