Sound system is the name used to designate speakers, amplifiers, music sources, the choice of the system depends on the desired area to install it and also the type of application intended.
The intensity of sound, "volume" is measured in decibels (dB).
There are basically three types of sound systems:
In these systems the volume should be just enough to be heard, not interfering in normal conversation of people, and should not be the centre of attention, not interfering in the business or leisure.
Such systems may be designed for residential or business:
Residential Environmental Sound
The evolution of these systems allows them to be used not only to spread music, but also to communicate between divisions, with integrated intercom, allowing calls to each individual division or general call to all rooms simultaneously, and one can also respond by the hands free system.
Features such as “baby-phone” are extremely important - when a sound is detected in the baby's room, the system emits a warning tone and switches the receiver (where it was listening to music) to the room environment sound, allowing alert parents when the baby cries, or the supervision of someone in need of special care (e.g. bedridden).
When equipped with the “Multi-Room” system, allows that each division can select the preferred sound source, regardless of the one that is selected in any other division.
Professional Environmental Sound
These systems are used to broadcast environmental music and information/emergency messages in hotels, schools, hospitals, public buildings, shopping malls, bus terminals, etc.
In these systems the study of the area to be sonorous is extremely important - the broadcasting system shall be uniform to prevent people closer to the speakers from being disturbed by its loud volume and the others, due to its low volume don’t ear it - is a mistake suppose that, when the area to be sonorous is big, you need to increase the size of columns or their power: the right is to put more speakers for a uniform distribution.
One of the causes of distortion and damage to amplifiers, transformers and loudspeakers occurs when a sound system designed for environmental sound is forced to situations for which it has not been designed or uses it as high pressure sound.
The columns used in these systems are generally compact, with small speakers (between 4 and 8 inches) and are specified for the commencement of work between the frequencies of 70Hz to 150Hz, thus, should be avoided in Environmental Sound frequencies below 80Hz.
Unlike the Environmental Sound, in this type of systems the sound is the main focus of attention, with high sound pressure and exaggerated frequency curves in their extremes. Generally prevents the normal conversation of people, but that's not important, since the main objective is the public's attention to the sound.
The speakers are usually 10-18 inches, with high volume and broad frequency response ranging from 20Hz to 20KHz.
This type of system is generally used in large events such as concerts, clubs, exhibition halls, stadiums, etc.
Hi-Fi Sound Systems
Hi-Fi (high fidelity) - This certification indicates that the equipment can accurately reproduce the sounds in the audible range for human beings, from 20 Hz (hertz) to 20 KHz (kilohertz); it’s the audio reproduction done by a stereo device with the highest fidelity to the actual sound, minimizing noise and distortion.
These devices make use of sound in stereo audio reproduction and the systems in which fidelity is the only commitment are known by the English term "high-end".
The stereo high fidelity devices use the minimalist concept in which is believed that the less sound stages between the captured, recorded, reproduced and amplified sound, the less will be the interference it’ll have related to the original and the greater will be their fidelity.
- The PABX