amplifier means the speaker,sound box.woofer what we generally used in our home.plese ans me.
2006-08-23 04:47:16 · 8 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
Amplifying is nothing but increasing the level. so any amplifier increases the sound level when used in conjuntion with sound box. In amplifier output israised proportionally and output/ input is called gain which is achieved by electronic circuitory.
2006-08-23 05:39:38 · answer #1 · answered by LodhiRajput 3 · 0⤊ 1⤋
Actually, a water faucet is like an amplifier. With a very small twist of the wrist you can greatly increase the flow of water under great pressure. In an electrical amplifier, a very weak signal from a microphone, phonograph needle, or radio antenna, etc. is used to control the flow of electrons under great voltage. Either vacuum tubes (called valves in England!) or semiconductors are used to control a current strong enough to drive a speaker (sound box or woofer). The amplifier replicates the received signal but makes it stronger (amplified). The speaker is part of an amplification system but only converts the strong electric signal to sound waves using electromagnets that move (vibrate) the paper cones of the speakers.
2006-08-23 06:31:25 · answer #2 · answered by Kes 7 · 0⤊ 0⤋
An amplifier can be considered to be any device that uses a small amount of energy to control a source of a larger amount of energy, although the term today usually refers to an electronic amplifier. The relationship of the input to the output of an amplifier — usually expressed as a function of the input frequency — is called the transfer function of the amplifier, and the magnitude of the transfer function is termed the gain.
Most amplifiers can be characterised by a number of parameter:
How much an amplifier increases the signal level is called the gain. This is usually measured in decibels (dB). Mathematically speaking, the gain is equal to the output level divided by the input level. (for power gain in decibels gain is computed by the relation G(dB)=10log(Pout/Pin)(Electrical)).
Output dynamic range:-
This is the range usually quoted in dB between the lowest useful output and the largest useful output level. Since the lowest useful level is limited by output noise, this is quoted as the amplifier dynamic range.
Bandwidth and rise time:-
The bandwidth (BW) of an amplifier is usually defined as the difference between the lower and upper half power points. This is therefore also known as the −3 dB BW. Bandwidths for other response tolerances are sometimes quoted (−1 dB, −6 dB etc.).
As an example, a good audio amplifier will have a −3 dB BW from around twenty hertz to about twenty kilohertz (the range of normal human hearing).
The rise time of an amplifier is the time taken for the output to change from 10% to 90% of its final level when driven by a step input. For a Gaussian response system (or a simple RC roll off), the rise time is given by:
Tr = BW/0.35, where BW is in Hz and Tr is in seconds.
Settling time and aberrations:-
Time taken for output to settle to within a certain percentage of the final value (say 0.1%). This is usually specified for oscilloscope vertical amplifiers and high accuracy measurement systems.
Slew rate:-
Slew rate is the maximum rate of change of output variable, usually quoted in volts per second (or microsecond).
Sine wave distortion:-
The properties of amplifier circuits distort the signal. This distortion comes in several forms including harmonic distortion and intermodulation distortion.
Noise:-
This is a measure of how much noise is introduced in the amplification process. Noise is an undesirable but inevitable product of the electronic devices and components. It is measured in either decibels or the peak output voltage produced by the amp
Efficiency:-
Efficiency is a measure of how much of the input power is usefully applied to the amplifier's output. Class A amplifiers are very inefficient, in the range of 10–20% with a max efficiency of 25%. Modern Class AB amps are commonly between 35–55% efficient with a theoretical maximum of 78.5%. Commercially available class D amplifiers have reported efficiencies as high as 97%. The efficiency of the amplifier limits the amount of total power output that is usefully available. Note that more efficient amps run much cooler, and often do not need any fans even in multi-kilowatt designs.
Linearity:-
An ideal amplifier would be a totally linear device, but real amplifiers are only linear within certain practical limits. When the signal drive to the amplifier is increased, the output also increases until a point is reached where some part of the amplifier becomes saturated and cannot produce any more output; this is called clipping, and results in distortion.
Some amplifiers are designed to handle this in a controlled way which causes a reduction in gain to take place instead of excessive distortion; the result is a compression effect, which (if the amplifier is an audio amplifier) will sound much less unpleasant to the ear. For these amplifiers, the 1dB compression point is defined as the input power (or output power) where the gain is 1dB less than the small signal gain.
Linearization is an emergent field, and there are many techniques, such us feedforward, predistortion, postdistortion, EER, LINC, CALLUM, cartesian feedback... in order to avoid the undesired effects of the non-linearities.
2006-08-23 05:08:47 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Definition: Amplifier is a Device which multiplies the given input signal with or with out taking external energy.
To a comman man amplifier is a box which is used to get a good quality of Sound/Picture in music system/televisison.
To all tech Bee`s a transistor is an amplifier but it is not exactly.
an amplier can be electronic or mechanical. it depends on wat type of physical quantity it is amplifing.
according to input physical quantity an amplifier can be classified as
Mechanical,electronic,etc.
eg: Electronic: op-amp, Transistor
Mechanical: bordan gauge,ponograph( which is used to draw maps in olden days), Bellows. some also many kind of linkages are there.
according to whether it is consuming energy or not it can be again classied as active and passive.
Active amplifiers: the amplifiers which dont require energy for amplification.
Passive amplifiers: The amplifiers which needs external energy to amplify the signal.
eg: if u observe an amplifier of a music system, u will be having an power cable i.e. it needs power to amplify so we can say it as passive amplifier.
i HOPE i have cleared the doubt!!!!!
thanks for yahoo!! and the person who asked me this question.....
2006-08-23 14:53:57 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Amplifier is electronic device, which is used to amplify a signal.
In general, amplifier are used in public speaker, in order to convert lower sound signal into higher one. Other application are to convert low power electrical signal into higher one, in Operational amplifier which is used to perform many mathematical operations, etc.,
In amplifier the amplitude is increased by required level, which consist of manly transistor,capacitor,resistor.
2006-08-24 03:02:59 · answer #5 · answered by Anonymous · 0⤊ 0⤋
actually amplifier is a system with following properteis:
It receives a signal as input then by consiming energy increases its amplitude and then you have the signal in output and canuse it
but I shuld imply that the signal is not necessarily sound it can be pressure light or even strain I hope you understand it well
2006-08-23 05:03:09 · answer #6 · answered by amin s 2 · 0⤊ 0⤋
amplifier is general term for increase level of input signal without change frequency .
current amp ,power amplifier ,if amplifier and bio amp ..etc
the amp is named as for specification.so function is same
2006-08-23 15:31:00 · answer #7 · answered by vazk 2 · 0⤊ 0⤋
they use transistors to amilify the electric power.for example the microphone is changed from sound to electricity by microphon then amplified by transistors and some amplifieng circuits then it is changed to sound by speakers
2006-08-23 05:02:10 · answer #8 · answered by nima_iran_1985 3 · 0⤊ 0⤋