|Converts sound into electric signals
The microphone is used to convert the sound produced by the voice or by an instrument into an electrical signal so that it can be adjusted, modified, and amplified by the system. The sound picked up by the microphone is converted from "acoustic sound" into "electrical signals" and then sent to the next device (the mixer) in the chain through a cable connecting the microphone to the mixer.
|Adjusts the sound that has been converted into electrical signals
The mixer is used to adjust the sound that was converted into electrical signals by the microphone. The signal level produced by the microphone is quite low so it must first be boosted in the mixer's "preamp" section. From here, the signal travels through the equalizer, which is used to adjust the tonal quality of the sound. The mixer also plays an important role in balancing the volumes between multiple microphones.
|Amplifies the Audio to drive the speakers
The power amplifier is used to increase the amplitude of the electrical signals received from the mixer's outputs so the speakers can reproduce the sound. The signal in the mixer is small, measured in milliwatts (or thousandths of a watt), too low for the speaker to convert into audio. An amplifier is used to increase this level into a much higher signal. Amplifiers are available from under 10 watts to over 1000 watts depending on the size of the system.
|Convert the electrical signals back into acoustic sound
Various types of speakers are tasked with this job. Some examples are; "Front Main Speakers" which are set facing the audience, and the "Sub Woofer" used to amplify very low bass frequencies. "Floor Monitors" are another type used to provide the performers with sound so that they can hear themselves along with the other performers.
Setting up the equipment
- Playing in a Band
Here’s an example of a PA for a band consisting of drums, bass, two electric guitars, a keyboard, and vocals.
- Small Music Group
This setup is a PA for a guitar and keyboard accompanying a vocalist.
- For Meetings
Here, the PA is for amplification in a meeting, using four microphones to allow many people to express their opinions.
- DJ Party
This PA is for an event where a DJ will be performing. In addition to a DJ mixer, we will also connect playback equipment such as an iPod.
PA equipment types
- Microphone types
A microphones is a device that converts sound into electrical signals. There are many types of microphone available for lots of different applications.
- Cable types
A variety of cables and connector types are used to transmit signals for different equipment and applications.
- Mixer types
There are several different types of mixer, including analog mixers, digital mixers, and powered mixers.
- Power amplifier types
There are a variety of power amplifiers, including stand-alone power amplifiers , powered speakers, and powered mixers.
- Speaker types
There are many different kinds of speaker, both passive speakers and self-powered speakers.
- What is reverberation?
Reverberation is an effect that brings out the depth and width of sound by adding numerous subtle echoes.
- What are compressors?
Compressors are effects that narrow the dynamic range (the difference between loud and quiet sounds) by compressing sound.
- What are equalizers?
Equalizers are effects that adjust tone by boosting and attenuating specific frequencies.