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Latest wireless audio gizmos such as iPods, wireless headphones and cell phones support new wireless protocols. These protocols are supposed to eliminate the cord and provide perfect high-fidelity audio. We will examine some of the most recent devices to figure out which applications they work for.

Several products come with wireless already built in while others, particularly streaming audio products, frequently have optional wireless functionality. Modern cell phones and MP3 players already come with support for wireless. iPhones and touch-screen iPods, for instance, have Bluetooth and WiFi.

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

1) Short range

Bluetooth usually just provides a 30 foot range. This is sufficient for single-room applications. On the other hand, this limitation does not permit multi-room streaming utilizing Bluetooth.

2) Audio compression resulting from limited data rate

Bluetooth will use audio compression because it does not reliably offer a high-enough data rate for uncompressed audio. The audio will be degraded to some degree as a result of the audio compression. For this reason higher-end audio equipment generally does not use Bluetooth wireless audio.

3) Signal latency

The signal broadcast via Bluetooth will undergo a slight delay of no less than 10 ms. This is mostly due to the audio compression. While being uncritical for MP3 players, this delay may be a dilemma for video and other real-time applications.

4) No support of multiple headphones

Bluetooth is relatively limited in regard to supporting streaming to multiple headphones. Streaming to multiple headphones is useful for numerous people wanting to listen to the same transmitter. This is less of a problem for MP3 player applications.

Uncompressed audio streaming is supported by WiFi. WiFi is a very widespread protocol. Yet, WiFi also has limitations regarding simultaneous transmission to several receivers. Due to the high availability, WiFi is suitable for streaming audio from a PC. However, WiFi products have relatively high power consumption. Because of this wireless headphones usually do not utilize this technology.

Wireless speakers and wireless amplifier products for home theater speakers typically utilize their own proprietary protocol. Entry-level wireless headphones and speakers usually still utilize FM transmission which offers low cost but is prone to noise and audio distortion.

More advanced wireless protocols are based on digital formats which eliminate audio distortion and incorporate sophisticated features including error correction to cope with interference from competing wireless devices.

Latest-generation wireless amplifiers employ uncompressed audio transmission. Recent protocols also allow streaming to an infinite number of receivers. This allows whole-house audio distribution.

Some of these protocols support low-latency audio transmission which ensures that the audio of all speakers will be in sync in a multi-channel application. Wireless audio transmitter products typically operate at 2.4 GHz or sometimes in the less crowded 5.8 GHz frequency band including Amphony’s wireless audio devices.

Wireless amplifiers are available with different levels of audio quality, power consumption and standby power. Getting a high-quality low-distortion amplifier is fundamental for good sound quality. Digital Class-D amplifiers offer high power efficiency of a minimum of 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 vital 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.

Car audio” is a term that refers no doubt to the sound system in your ride, be it a van, car, or truck. To some people, car audio is very much part and parcel of their car as a whole. Some even try to make a casual estimate of the car’s worth by checking out the specifications, features and company of the car audio. Some cars have stock car audios designed for the vehicle by high-quality makers while some prefer to have specially built car audios, i.e. any audio system simply won’t do if it is not from a car audio of the company they have come to trust through the years. Behind any auto audio system are the acknowledged essentials, namely: a radio/FM, and a CD/DVD player. Such a system is nowadays expected no less to be able to support widely used formats such as MP3, WMA, CDA, etc. Up to date car audios also boast of catering to USB, Wi-Fi and Bluetooth connectivity fans.

A good car audio is known as the default and the through-and-through solution when it comes to dealing with the staples of fatigue and boredom which go hand in hand with long-haul trips. When you have a good and trusty car audio with you, time simply flies, and is at best, some sort of distraction. A versatile car audio can be counted on when users want to stay wired to the latest headlines, events and traffic updates as well as their favorite programs on the radio.

These days, the car audio market is in the middle of shifty ground when it comes to quality and demand. Technological boosts and advances in the car audio segment not only lead to the better quality of even off-the-shelf car audios, but also eventually mean considerable leaps in the volume of car audios sold. A competitive crowd of players are now out in the market and all struggling to get the most attention by touting high quality playback and enhanced bells and whistles.

Discerning audio lovers nowadays try to get the best possible value-for-money in-car entertainment. High end audio equipment–with makers like Blaupunkt, Sony, Alpine, Pioneer and Kenwood–sure to meet the demands of the strictest audiophiles helps the various competing brands to stay razor-sharp and keeps the market stocked with quality.

So do you have the car audio unit all cut out in your mind? Is it equipped with basic speakers and signal processing equipment, or is something in you screaming to still go for extra speakers, subwoofers, amplifiers and tweeters? As the features-wars continue, company-makers also thrown into the package perks like amplifiers and speakers to their car audio kits. But how do you know if you got in front of you a good quality car audio? Check and double check that it must be able to play unwavering and skip-free tracks while the car is on the go. Let’s face it, these lives and times are spoilt for choice when it comes to picking a car audio system from the myriad of options available, whether online or just around the corner. But always keep in mind to steer clear of buying unbranded and substandard car audios that will pile up problems and costs on you much later on.

The latest series of wireless audio transmitter devices promises streaming of music throughout the home without limits. We will look at various products and technologies to find out in how far these devices are effective for whole-house audio applications and what to look out for when buying a wireless system.

Infrared wireless audio devices are restricted to line-of-sight applications, i.e. only function within a single room because the signal is sent as infrared light which can’t penetrate walls. This technology is often found in wireless speaker kit products.

RF wireless music devices broadcast the music signal via radio waves. These radio wave signals can without difficulty go through walls. The signal is broadcast either by utilizing FM transmission or digital transmission. FM transmission is cheap but quite prone to static, audio distortion and susceptible to interference.

Digital wireless audio transmitter devices, such as products from Amphony, make use of a digital protocol. The audio is first converted to digital data before being broadcast. This method guarantees that the audio quality is fully preserved. Some transmitters utilize some form of audio compression, such as Bluetooth transmitters, which will degrade the audio to some degree. Transmitters which send the audio data uncompressed will achieve the highest fidelity.

Wireless LAN (WLAN) products are practical when streaming from a PC but will add some amount of latency or delay to the signal because wireless LAN was not originally designed for real-time audio streaming. WLAN receivers ordinarily require buying a separate LAN card to be plugged into every receiver.

Powerline products send the audio via the power mains and offer great range. They run into problems in homes where there are individual mains circuits in terms of being able to cross over into another circuit. Also, these products build in a delay of a number of seconds to safeguard against transmission errors during power surges and spikes which prevents their use in applications where the audio from wireless loudspeakers has to be in sync with other non-wireless speakers or video.

Here are some recommendations for picking the optimum wireless audio system: Try to find a system that can run several wireless receivers from a single transmitter. Ideally an unlimited number of receivers should be supported. That way you don’t need to buy extra transmitters when you start adding receivers in several rooms of your house. Some devices have some form of error correction built in which will help guard against dropouts in case of strong wireless interference. Choose a digital RF audio transmitter to guarantee that the audio quality is preserved. Make sure the audio delay is smaller than 10 ms if you have a real-time application such as video.

Select a transmitter that has all of the audio inputs you need, e.g. speaker inputs, RCA inputs etc. Get a wireless system where you can buy separate receivers later on. You should confirm that you can get receivers for all the different applications you have. Such receivers may include amplified receivers for passive speakers or line-level receivers for active speakers. Select a transmitter that can regulate the audio volume of the input stage. This will give you the flexibility to connect the transmitter to any kind of equipment with different signal levels. Otherwise the audio may get clipped inside the transmitter converter stage or the dynamic range is not fully utilized.

Check that the system provides amplified receivers with a digital amplifier to ensure high power efficiency. This will help keep the receiver cool during operation. Also, make sure the amplifier provides low audio distortion. This is vital for good sound quality. Verify that the amplified receiver is able to drive speakers with the preferred Ohm rating and that it is small and easily mountable for simple installation. Products using the less crowded 5.8 GHz frequency band will normally have less trouble with wireless interference than 900 MHz or 2.4 GHz products.