What is an Amplifier?

So you know amplifiers exist and you may even know that they are an important thing not only in the world of audio but also in many other applications like RF radio, video, and all the way through to broadcasting and electronics in general.

Don't worry, this isn't going to be a geeky, scientific explanation of the science behind amplification. This article is simply your introduction to the magical world of amplifiers and how they have transformed the world we live in, without the geek-speak! Without amplification, we would have no telephony, internet, live and recorded music, computers, and that's without even touching on the world of medical technology. The invention of amplifiers was crucial to everything the modern technological world can offer. So, what does an amplifier do and what is it used for?

In essence, an amplifier is a device that increases the power of an electronic signal. For most of us, we are familiar with the role of amplifiers in their ability to amplify the sound from musical instruments, like guitars and pianos, as well as vocals. Amplifiers are also used in some types of speakers. An amplifier can make low volume sounds louder or high volume sounds quieter by increasing or decreasing their power respectively. The term "amplifier" is often applied to both electrical and acoustic devices which accomplish this function.

What is an Amplifier Used For?

Electrical amplifier devices are used in a wide range of products and industries. These include electronic and stereo equipment, recording studios, concerts, and live music venues, computer speakers or headphones, as well as some types of home theatre systems.

Electric amplifier applications can be divided into two main groups - analog amplifiers and digital amplifier technology. Analog amplifier technology uses different types of amplifier devices to control the electric signal flow through a circuit. The most basic amplifier designs use transistors, vacuum tubes, and other electrical components. Digital amplifier technology on the other hand uses digital circuits, which are usually combined with analog amplifier designs.

Digital amplifier technology is used in products like CD players (which can only be made using digital amplifier circuitry), computers, televisions, and many other things - the list is endless! Digital amplifiers replace older vacuum tube amplifiers in some cases, especially where there is high-quality sound output required as well as minimal heat produced from the amplifier device itself. Amplifier circuits can also be found designed into audio processing equipment such as reel-to-reel tape decks or even cassette players (like the one you had when you were younger!).

Digital amplifier technology was developed partly because of its ability to store and process audio recordings in memory before it is amplified by transistors. This can produce a much better quality sound than an amplifier that simply reacts to an incoming signal. The amplifier device typically amplifies the power level of the electrical signal input in real-time, acting as a pass-through of sorts for whatever signal it receives while operating at high speed without any need for processing or delayed action. Both analog and digital amplifier designs are capable of producing very strong voltages which increases their value for things like electric guitar amplification systems (a good amplifier will be loud enough to counteract the high noise levels produced by a distorted amplifier).

How amplifiers work to strengthen sound signals and make them louder

To try and understand in layman's terms how an amplifier strengthens and makes sound signal louder, try thinking of it as a black box that takes a low voltage or current waveform (sound wave) in and then increases the amplitude of this waveform. In so doing the loudness of this when played through loudspeakers increases. This is called increasing the gain of a signal. This also introduces artifacts like increased noise levels, distortion, etc. A good amplifier will work to decrease the worst of these artifacts but depending on the application, some are welcome. Ask a rock guitar player about distortion levels!

All amplifier devices have a specified impedance which indicates their effectiveness in transferring signal power and resisting electrical current flow. The more effective an amplifier is in doing this, the better it will be at its job. This means that low impedance amplifier designs are usually preferred as they tend to produce lower noise levels.

The amplifier acts as a voltage amplifier to aid in the increase in signal strength and it does this using techniques such as resistors in conjunction with transformers. If you are very interested in electronics, you will know that these two methods are commonly used in amplifiers because they help to reduce amplifier noise levels by limiting current flow through the amplifier circuitry.

What is amplifier gain? AC amps have an inherent part of their design called the feedback loop which is used to give the amplifier device stability and self-regulating action over its performance level. It works by allowing some of the output from the amplifier channel back into its input so that any abnormal variations can be canceled out before they become problematic for either circuit operation or external sound quality.

Different Types of Amplifiers

A power amplifier is a device that uses active devices, such as transistors, to increase the amplitude of an electronic signal before transmission. These amplifiers are used in both communications and broadcasting applications because they can amplify signals to a high power level before they are transmitted into the air.

An audio amplifier is an electronic device that increases the amplitude of sound waves to drive a loudspeaker to produce loud sounds in music, as well as film and television productions. The main use of audio amplifiers is for musical performances or home theater systems. Audio amplifiers can be used with an instrument such as a guitar or microphone or a CD player to produce sounds inaudible frequencies that the human ear can hear.

An RF amplifier is designed to operate over a broad range of frequencies, typically anywhere from less than one megahertz (MHz) up into the hundreds and higher. In communications applications, these amplifiers are the final stage in the power chain. They are used to convert a low-level, high-power microwave signal into a radio frequency (RF) signal that can be sent over the airwaves.

The Benefits of Using an Amplifier On a Signal

An amplifier's main job is to increase the power of a signal so that it can be transmitted over long distances without degradation and so that small signals can fill a larger area. This means that an amplifier provides many benefits:

• Amplifiers are used in communications systems to boost gain at low levels

• Broadcasts television and radio signals over long distances

• Amplifiers provide large amounts of gain without distortion, making them ideal for musical instruments like guitars or microphones because they improve the level of the sound without adding any unwanted noise or static - for example: recording studios or music venues.

The Disadvantages of Using an Amplifier On a Signal

Amplifiers can sometimes cause unwanted distortion or add noise to a signal being amplified. This is especially true at the higher levels of gain that are used in communications systems. To counteract this unwanted distortion, manufacturers created a linear amplifier that can process signals without adding noise or static.

Modern Amplifier Use In Communications

Every time you turn on your television or watch a TV show or listen to the radio, you use an amplifier to amplify your signal over long distances so it can be received by hundreds of people. These amplifiers are used in television broadcasts, radio signals, as well as cell phone transmission towers.

A cell phone tower uses microwave long-haul signal amplifiers to boost your TV or radio station broadcast into a stronger signal that can be picked up by the antennas on your cell phone. Large commercial buildings use microcell amplifier systems to provide coverage inside large structures like malls.

When You Should Not Use An Amplifier On a Signal

There are times when you should avoid using an amplifier on your signal, including:

• You have audio frequencies that are too loud or quiet to be received by the intended audience. An audio amplifier can help boost these weak signals by increasing their gain. However, some low-level frequencies can become so loud that they distort into a higher level of noise – this is called overloading. In this case, it is best to keep your sound levels at a moderate volume and use only clean amplification equipment.

• You are amplifying a signal that has very low audio frequencies. Amplifiers are more difficult to construct at the very low, subsonic frequencies, and most sound equipment today does not have the power or type of amplification needed for these types of signals. You

• If you are using a sound system in which you want to amplify the overall level of the whole system, it is better to use a line-level amplifier instead. These types of amplifiers have little emphasis on any one frequency range, resulting in less distortion as sounds combine with each other. A preamplifier also allows for easier signal processing because its output can be switched among different frequencies that are boosted or cut during the performance.

Summary

With the many benefits of amplifiers, it is no surprise that they are used for many different types of projects. Amplifiers are critical for boosting signal strength in order to send signals over long distances or to fill an area with a strong signal, and they can be instrumental in improving the sound quality of performance. Despite their convenience and usefulness, you should be aware of how an amplifier could affect a particular type of application (audio, video, communications) and base your buying decisions on proper research.