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A Look At Some Of The Coolest Wireless Audio Devices

Latest-generation wireless audio products such as iPods, iPhones and wireless surround sound products promise to cut the cord while delivering crystal-clear audio. I will look at a number of the latest gadgets and technologies to learn how well they work and in which situations they work best.

A number of products are available with wireless already built in while others, particularly streaming audio products, often have optional wireless ability. Latest generation iPods and cell phones already come with built-in WiFi and Bluetooth support.

Bluetooth is fairly common as a low-cost wireless option. Nonetheless, Bluetooth does have some drawbacks. These weaknesses are often ignored but will have an influence on high-quality audio applications.

1) Restricted operating range

Bluetooth usually only provides a 30 foot range. This is enough for single-room applications. However, this limiting factor does not allow multi-room streaming using Bluetooth.

2) Low data rate – audio compression

Bluetooth reliably supports data transmission rates of around 1 Mbps only which is not sufficient for uncompressed CD-quality audio. Thus Bluetooth uses audio compression. Audio compression will deteriorate the audio quality to some degree. High-quality audio transmission normally does not tolerate this type of degradation. Therefore Bluetooth is typically not used in high-end audio devices.

3) Audio latency

The signal broadcast via Bluetooth will bear a slight delay of a minimum of 10 ms. This is for the most part attributable to the audio compression. While being uncritical for MP3 players, this delay may be a dilemma for video and other real-time applications.

4) Lacking multi-headphone support

Bluetooth can’t stream to numerous headphones at the same time. This might be a dilemma in cases where numerous people like to listen to the same Bluetooth transmitter.

WiFi is one more widely used wireless protocol that is also suitable for audio streaming. WiFi does support uncompressed audio but will have problems transmitting to a large number of wireless receivers simultaneously. Due to the high availability, WiFi is convenient for streaming audio from a PC. On the other hand, WiFi products have fairly high power consumption. Because of this wireless headphones usually do not utilize this technology.

Home wireless speaker devices and wireless amplifiers generally utilize proprietary protocols. These protocols are specially engineered for real-time audio applications. On the other hand, low-cost wireless speakers and headphones still utilize FM transmission. FM transmission suffers from fairly high audio deterioration and noise / static.

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

Latest-generation wireless amplifiers utilize uncompressed audio transmission. New protocols also allow streaming to an unlimited number of receivers. This allows whole-house audio distribution.

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

Wireless amplifiers offer different levels of audio quality, output power and standby power. Digital amplifiers generally offer a power efficiency of no less than 80% and standby power consumption of less than 5 Watts which keeps them cool during operation and helps save energy. However, some Class-D amps have fairly high audio distortion. Audiophile wireless amplifiers offer an audio distortion of 0.05% or less.

Crestron Sonnex HD Audio Distribution