Advice For Discovering The Best Audio Amplifier

By Brian Fuller

Picking a good audio amplifier for your speakers is not a trivial task. You want to ensure that your amp matches your speakers. I will explain some basic amplifier terms and give some pointers to help you pick the best amplifier.

There is a flood of different audio amplifiers available which all differ in their specifications, shape and size. However, you don't need to be an expert to pick the best model. By following some basic rules you won't regret your buying decision.

The most apparent parameter is the size of the amplifier. There are models that are as big as half your living room while some of the newest mini amplifier models are as small as a bar of soap. A large number of amps are the size of a standard rack. This allows your amp to be stacked on top of your other audio devices.

There are some core amplifier technologies available. One technology is called "solid-state". Solid-state amps now account for the majority of audio amplifiers. In the past, tube amplifiers have been popular. Even today tube amplifiers are still available. Tube amplifiers, however, have a fairly high amount of harmonic distortion. Harmonic distortion refers to how much the audio signal is degraded while being amplified. This term is often used while comparing the audio quality of amplifiers.

An audio distortion of up to 10% is typical for tube amps while solid-state amps have lower audio distortion depending on the particular technology. In the past, mostly "Class-A" and "Class-AB" amps were available which are also known as "analog amplifiers". While amplifiers using these technologies typically have low audio distortion, power efficiency is only 10% to 30%. Power efficiency refers to how much of the electrical power is actually used to amplify the signal. The remaining portion is wasted as heat. An amplifier with low power efficiency will radiate most of its power as heat.

"Class-D" amplifiers, however, which are also called "digital amplifiers" have a power efficiency of at least 80% and are smaller and have a smaller power supply than comparable analog amplifiers. The downside is that many digital amplifiers have higher audio distortion than analog amplifiers although some of the latest models employ a feedback mechanism to reduce distortion to levels of 0.05% and below.

Your amplifier should deliver sufficient power to drive your speakers. The amount of power will depend on the power handling rating of your speakers. Another factor is the size of your room. There are two values for speaker power handling: peak and average power handling. The peak value shows how much power the speaker can handle for short periods of time. The average value on the other hand describes how much power the speaker can tolerate continuously without damage.

In a small listening environment, you may not need to drive your speakers to their rated value. 20 to 40 Watts of power will probably be plenty. Speakers however differ in their impedance and sensitivity. As a rule of thumb speakers with low impedance offer higher sensitivity. High-sensitivity speakers are easier to drive to high volume than low-sensitivity speakers. Not all amplifiers can drive any speaker impedance. Find out the impedance of your speaker which is given in Ohms. Then look at your amplifier manual to ensure that your amp can drive this impedance.

Lastly, make sure that your amplifier introduces little noise and has a broad enough frequency response. High-quality amplifiers will have a signal-to-noise ratio of at least 100 dB and a frequency response of at least 20 Hz to 20 kHz.

About the Author:

You can get further information regarding audio amplifier technologies at Amphony's website.

Is AOL Radio Going To Cause The Extinction Of Traditional Stations?

By Brian Fuller

Online radio such as AOL Radio, Slacker, Pandora and Last.fm have gained popularity lately. In addition, many wireless devices such as mobile phones support these platforms. Are local radio stations doomed? I will take a closer look at online radio to try to answer this question. In particular I will examine the impact of online radio on local broadcasters.

I appears that local radio stations are on their way to become extinct. They are being threatened by the advance of online and satellite radio. These competing services typically offer hundreds of music and entertainment channels. Some of the channels are even commercial-free. The internet has enabled access to a virtually unlimited number of online radio channels.

Pandora and other online radio services have become available of wireless audio devices by installing the appropriate app. This increases convenience and mobility of online radio. Mobility has thus far been the biggest advantage of local radio.

AOL Radio uses CBS radio as its broadcasting platform. It comes with over 200 music channels. In addition it offers access to more than 150 local CBS radio stations. The underlying CBS radio platform "play.it" also allows listeners to create their own customized music channels. This is done by entering the names of albums, tracks or artists. The tracks played on each music channels can also be stored on an iPod for later playback by using 3-rd party tool iGetMusic.

Pandora and other online radio services have similarly started to offer customize music. The user can enter music-related information such as artist, track or album name. These channels will then select tracks which are similar to the information entered. Thus far, however, competing music services have fallen short from offering similarly fully customized radio channels.

Does online radio mean the end of local radio? The growing number of options clearly is going to shrink the market share of traditional radio broadcasters. Online radio is particular useful for niche broadcasters who have been unable to broadcast due to the high cost and licensing of frequency space.

Online radio broadcasters have found it difficult to be profitable. The main reason is the huge number of competing channels which is diluting listeners. The lower cost of online radio at the same time allows creation of more appealing content than local radio by serving niche markets and inserting fewer commercials.

Local programming such as news and local events, however, will remain one of the big advantages of local radio. Thus far the poor audio quality of FM radio has been a big drawback. However, new digital radio broadcasts are set to improve the audio quality. One of these technologies is HD radio. Content and mobility will be crucial in determining the fate of online and local radio. Online radio offers a large number of choices while local radio excels by supplying local content. Both online and local broadcasts offer great mobility. Therefore it is hard to predict a clear winner in this radio battle.

About the Author:

You can find additional details regarding AOL Radio and wireless audio products at Amphony's website.

A Glance At Some Of The Coolest Wireless Toys

By Brian Fuller

Lately a large number of wireless audio products have emerged such as latest-generation wireless headphones, iPods, cell phones and wireless amplifier products which promise to cut the cord. I will take a look at some of the newest gadgets and technologies to find out how well they work and in which situations they work best.

Products can be categorized into products with built-in and those with optional wireless capability. Streaming audio products will often have a plug-in slot for adding a wireless LAN card. Latest generation iPods and cell phones already come with built-in WiFi and Bluetooth support.

The Bluetooth protocol is a fairly low-cost solution. However, its drawbacks have an impact on high-quality audio applications and are often overlooked.

1) Short range

Bluetooth normally only offers a 30 foot range. This is sufficient for single-room applications. However, this limitation does not allow multi-room streaming using Bluetooth.

2) Limited data transmission capacity

Bluetooth will apply audio compression since it does not reliably offer a high-enough data rate for uncompressed audio. Audio compression will degrade the audio quality to some extent. High-quality audio transmission typically does not tolerate this type of degradation. Therefore Bluetooth is normally not used in high-end audio products.

3) Audio latency

The signal transmitted via Bluetooth will undergo a slight delay of at least 10 ms. This is mostly due to the audio compression. While being uncritical for MP3 players, this delay may be a problem for video and other real-time applications.

4) Lacking multi-headphone support

Bluetooth does not support any number of headphones which may be a problem if you have a larger number of people who want to listen to headphones from a single transmitter device.

Uncompressed audio streaming is supported by WiFi. WiFi is a very common protocol. However, WiFi also has limitations in regard to simultaneous transmission to several receivers. Due to the high availability, WiFi is convenient for streaming audio from a PC. However, WiFi products have fairly high power consumption. For this reason wireless headphones typically do not use this technology.

While newest-generation wireless speakers and wireless amplifier products use proprietary digital technologies, entry-level products often still rely on FM transmission which is noisy and has high audio distortion and high susceptibility to radio interference.

More recent wireless audio protocols are based on digital transmission. This avoids audio degradation. Some protocols also incorporate error correction to deal with interference from other wireless devices.

Advanced wireless amplifier devices support uncompressed digital audio streaming to preserve the original audio quality. Some of these protocols allow streaming to an unlimited number of wireless amplifiers which is convenient for whole-house audio distribution. The audio latency ranges from below 1 ms to up to 20 ms. A small latency is important for wireless surround sound applications. These wireless audio transmitters typically work at 2.4 GHz. There are also some products such as Amphony's line of wireless audio products which work at 5.8 GHz. Products that operate at 5.8 GHz have less competition from other wireless devices than those using the crowded 2.4 GHz frequency band.

Wireless amplifiers are available with different levels of audio quality, power consumption and standby power. Having a high-quality low-distortion amplifier is vital for good sound quality. Digital Class-D amplifiers offer high power efficiency of at least 80%. They also have low standby power, typically less than 5 Watts. This reduces heat and keeps them cool during operation. Some digital amplifiers, however, have fairly high harmonic distortion. It is important to select a wireless amplifier with low audio distortion. This will ensure good sound quality. High-quality amplifiers have audio distortion of 0.05% or less.

About the Author:

You can find further details regarding wireless audio products at Amphony's website.

Digital TV Aerial Installers- How to find Quality Installers

By Henry Mangult

Many people who are attempting to find digital TV aerial installers have been plagued by the same questions that you may be asking yourself during your hunt to find the high-quality digital TV aerial installers that you want working on your home or business TV set. What should the installation service cost? How long will the installation take? Does my aerial system just need an upgrade or does anew aerial need to be installed altogether? By doing your research ahead of time you'll be able to locate digital TV aerial installers who can answer your questions and provide you with the aerial installation of your dreams.

Even though they're probably many digital TV aerial installers in your region you still have to go thru the process of weeding out contractors who are only looking to make a quick buck. Making sure to find digital TV aerial installers who can answer your questions and look out for your best interest while providing a fair price can be hard to do, however here are several steps that you can take to prevent from being taken advantage of.

Ask the questions that you want to know and expect to receive good concise answers that put you at ease. If you receive answers that seem odd or if the digital TV aerial installers seem reluctant to answer all of your questions fully and completely you may want to consider a new batch of digital TV aerial installers to begin interviewing. You should not only feel comfortable with the responses that you received but you should also never feel pressured to buy right away. The "hard-sell" is often a tactic used to by underhanded contractors looking to prey on the unsuspecting clientele.

Another great indicator of quality digital TV aerial installer is their willingness to stand by their work. Whether it is for a home installation or business installation many good digital TV aerial installers will offer some sort of warranty behind the hardware and service that they have provided. It is always reassuring to know that with a simple phone call you will have the installer back at your home and doing the needed repairs without cost to you.

At the end of the day the choice of digital TV aerial installers is one that you must make on your own but by using the hints and tips provided above not only will you be more likely to pick a high quality digital TV aerial installer but you also rest easier with the knowledge that you've done your research and homework prior to picking an quality installer.

About the Author:

Want to find out more about aerial installers in London, then visit Henry Mangult's site on how to choose the best digital TV aerial installers for your needs.

Sirius vs. XM Satellite Radio Compare: Which One Is Better For You?

By Matt Barns

We have all heard of the two major satellite companies available today, Sirius Radio and XM Satellite Radio. Many people, maybe even you, don't even know that much about them such as costs or what is even available on a satellite radio. They are tired of listening to the old AM and FM standard radio stations for valid reasons. Many FM and AM radio stations publish long waits with commercials. Whichever reason it may so be, people are turning to satellite radio more and more than regular radio stations.

Both companies are able to offer you static free radio due to satellites. XM (based in Washington D. C. ) has two and Sirius (based in New York) has three satellites across the United States. Both companies offer users commercial free radio. Sirius offers over 125 channels and XM offers 160 different channels. There are dedicated channels for genres of music such as jazz, folk, country and pop for die-hard fans. One cool feature of satellite radio is you can see the name of the artist playing as well as the song title. So never again do you have to spend time wondering just who sang that song you just heard! There are also channels for local weather and traffic, sports, comedy, women's issues, talk shows, even old time radio shows. Soon, you may be able to see video as well as hear audio on your satellite radios.

Celebrity shows exist for both XM and Sirius radio companies. The celebrity, Martha Stewart recently signed a deal to launch a 24-hour radio channel on the Sirius network. Howard Stern is also another famous figure on the Sirius network. Howard Stern, having been into trouble with the FTC for his show, decided to jump to uncensored airways of satellite radio. Since his decision to do so, his subscriber base has increased by a minimum of 2.7 million. If you have satellite radio and would like to hear National Public Radio, You will have to subscribe to Sirius as they are the only company offering the service.

It all sounds wonderful, however, what do you really need item wise to receive satellite radio? Well, You have to acquire either a Sirius or XM radio system. It does not have to be a radio for use in your car either. Home radios are available today and there are dual systems you can use in your home or your car. A price for a basic setup of the radio offered by both can be as low as $49. 99. You will need to subscribe for a service, however. Each company charges $12.95 a month for you to receive satellite signals on your radio. You can save, however, using a family plan available for both companies.

Just how popular is satellite radio becoming? In March of 2005, Hyundai announced that it would be the first automaker to put satellite radios in all of its models sold in the United States. Each Hyundai, including the popular Sonata, Santa Fe, and Elantra models, will come equipped with an XM satellite radio. When this was announced, shares in XM's parent company rose by more than 8 percent. Jaguar and Mercedes-Benz also announced in March 2005 that Sirius radios would be a dealer-installed option on some of their models.

So which satellite radio should I choose, you ask? It depends on you. You should check out the stations available by visiting the company website before any decision is made. Both of them are offering the radio at comparable prices, so it really comes down what you want to hear. Are you a fan of Stern? Then you have to go with Sirius. But if you love Oprah, you can listen to her on Oprah XM. Regardless of which one to choose, you will definitely be very pleased with either of the services and/or satellite receptions.

About the Author:

Want to find out more about Satellite Radio Subscription, then visit Matt Barns's site on how to choose the best Satellite Radio Company for your needs.

Aerial Service- Getting Good Picture Quality

By James Sollis

Every homeowner will have a need at some point to either install a new aerial or to have the one they currently have repaired or upgraded. At this point, they will need to locate an aerial service company that can get the job done. Not being able to enjoy your favorite TV shows may mean that your aerial is not functioning properly.

Sometimes there are strong winds or trees may grow up and block your signal area. Any reputable aerial service can examine your aerial and deal with any problems and have your aerial back in business so that you can again view your TV when you want to.

Most of us have a hard time not being able to view our favorite programs, as TV has become part of our every day lives and we all enjoy viewing our favorite programs daily or weekly. Having the best aerial service from the beginning, at the point you initially install the aerial to having repairs done is very important.

Perhaps you would like to have a new aerial service installed or your current one upgraded. Either way, you should be able to get some input from a good company. They should be able to assist you in making the right choice in an aerial that will serve your needs best. There are a lot of different choices when it comes to aerials, so you need to make sure you choose the right one.

Digital TV is the latest service being provided by cable companies, and you will need to have a digital aerial to receive this service. Most cable companies have discontinued analogue broadcasts, so you will need an upgrade in order to receive a signal. Sometimes you can get an aerial service company to install digital aerials for around the same price as you paid for an analogue aerial, as the wiring has already been run and there is not much extra work involved.

About the Author:

Looking to find the best deal on aerial installers london, then visit www.londonaerialsystems.com to find the best advice on freeview aerial installers for you.

Is It Worth Getting A Two-Way Radio?

By Fabina Barorelli

There are many different uses for two-way radios. Personal use is probably the type most people are familiar with. Children use them as toys to play with in the yard or in the neighborhood. Most of us played with walkie-talkies at one point when we were growing up. Other personal uses include keeping in touch with your family members on a regular basis. Maybe your kids are going to play at the neighbor' house and you want to stay in touch with them.

Sometimes families will use them on camping trips or vacations to the beach simply as a way to be in easy reach of each other. Sometimes people who live in large houses use them to talk to the kids in the backyard or talk to other family members located at the other end of the house. Many will hooked them on their kids bicycles so that they can stay in touch with them while they are out with their friends. Obviously, these are just a few ways people use two-way radios for personal needs, but they are some of the more common uses.

Businesses use two-way radios as a matter of course. These devices provide the best way to communicate when people are working within a small radius but still are not within shouting distance. Many factories use them to connect loading docks with other departments through out the facility. This prevents people from having to run around all day long trying to locate other workers. They simply make working, more productive in these situations.

Two-way radios are more dependable for use in emergencies anyway. They don't have to pick up a signal from a cell phone tower. They are typically not dropped like so many cell calls are. The voice clarity is usually much better on a two-way than it is on a cell phone. More than one person can get a message with a two-way than with a cell phone also. If the side of a building that is on fire, is about to fall down, you want to be able to relay that message to all the firefighters at once, not one at a time.

Businesses are big users of two-way radios. Obviously, they will only work for others people who are working in the same location of a company. They will not carry from one company location to another that is located 300 miles away. But within a location they are a more reliable and convenient way of communicating between different departments, etc...

UHF two-way radios are used in high rise buildings because their signals have the capability to penetrate threw walls and floors and other obstacles to connect with the other users in the building. Restaurants use two-way radios to communicate with delivery drivers. Local delivery services use two-way radios in order to provide better service to their customers. Local delivery trucks are another example of a business use for the radios.

There are many other examples of business uses for two-way radios. They are however, a tool that can make any business more efficient and productive. The use of two-way radios is likely to continue a steady growth because of the reliable service they provide, whether for business, personal or emergency services.

As you can see, there are many different uses for two-way radios. The uses mentioned in this article are just a few. There are many others as well. Any place where people need to be in easily reachable within a localized area, the radios are one of the best ways to stay in touch.

About the Author:

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