Many PA speakers deliver clear and well balanced sound, but other speakers must be adjusted. They may deliver a sound that is fuzzy, humming, or has a high frequency screeching sound. Some speakers in a common system may simply be dead. In all these cases, the speaker will need to be tested and adjusted.
In a system where volume from all its speakers is too low, you can adjust the volume control knob on the amplifier that supplies electronic sound impulses to the system speakers. This low volume, however, can also be caused by the use of an amplifier that has insufficient power. In a warehouse or industrial environment, for example, the amplifier should be able to deliver 10 watts of power for each speaker connected to it. A system with eight speakers, for example, should be served by an 80 watt amplifier. There may be, however, a third reason for low volume. If each speaker is installed with a transformer, the transformer may need to be adjusted for power it delivers to the speaker.
Speaker location in a PA system, referred to by industry pro's as a sound system, must be engineered by technicians knowledgeable in sound system engineering. Location of speakers affects sound quality because of sound speed. If you are standing at one end of a large area with one speaker near you and the other 100 feet away, you will hear sound from the nearby speaker a split second before you hear sound from the distant speaker. This difference can create sound distortion. If this is the case, you will need to re-direct the speakers or add additional speakers to get better coverage.
When speakers are too close to a microphone that produces the sound broadcast over the speakers, you will often hear an ear-piercing, high frequency noise. When this happens, you can switch to a directional microphone, lower the speaker volume or redirect the speaker.
PA system amplifiers are designed to deliver a pure electronic signal to the speakers that receive these signals. When electrical interference is introduced into these signals, such as an electric short, you will often hear this interference as a hum being broadcast from the speaker. You will then need to examine the connections and wiring from the speaker to the amplifier, find the short, and repair it.
At times you may hear radio station transmissions broadcast through your PA system speakers. These transmissions, called RF (radio frequency) are sometimes picked up by speaker wires that deliver sound to the speaker from the PA amplifier. When this happens in your PA system you can usually correct the problem by replacing your common speaker wire with shielded wire.
When a speaker in your PA system is dead, it usually means you have a bad wire connection. This connection problem can be at your speaker or at the amplifier. It can be caused by a severed speaker wire. You should inspect your wire and repair the connection or splice your severed wire.