10.Walk outside — look at the horizon. See any radio towers? Locate potential sources of RF interference and plan for them before you begin construction. Know the frequency, transmitter power, etc. You can get this information by calling the station. Remember that many broadcast stations change the antenna coverage pattern and transmitter power at night.
11.Don’t use
12.Don’t allow for anything other than micro- phone inputs at stage/altar locations. Supplying line inputs at these locations is an invitation for misuse. Make all sources look like microphones to the console.
13.Balance (or at least impedance balance) all connections that are remote from the console’s immediate location.
GROUNDINGGrounding exists in your audio system for two reasons: product safety and noise reduc- tion. The third wire on the power cord exists for product safety. It provides a
The metal chassis of the product, the ground connections provided by the various connectors, and the shields within your connecting cables provide a
Many “authorities” tell you that shields should be connected only at one end. Sometimes this can be true, but for most (99%) audio systems, it is unnecessary. If you do everything else correctly, you should be able to connect every component of your audio system using standard,
Here are some guidelines:
1.Use balanced lines if at all possible. They provide better immunity to induced noise and ground loops. Remember that you can balance a line by inserting
2.Avoid using
3.Be sure all AC outlet safety grounds are connected to one common point in a star ground arrangement. This common ground point should then tie back to earth ground at the service entrance by one heavy stranded wire, #2 gauge or larger.
4.Don’t cut the third pin off the power cord. Carry some
5.Cables that are too long are less likely to pick up hum if you uncoil them in their entirety, and then find a place to stow the excess. Leaving the excess coiled only helps the cable pick up hum more efficiently.
6.If you bundle your cables together, don’t bundle AC wiring and audio wiring to- gether. Bundle them separately.
7.If your sound system insists on humming, you may want to teach it the words.
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