A Glance At A Few Of The Coolest Wireless Audio Toys
Newest wireless audio gadgets such as iPods, wireless headphones and cell phones support newest wireless protocols. These protocols are supposed to cut the cord and provide perfect high-fidelity audio. I will have a look at a number of the latest gadgets and technologies to discover how well they work and in which situations they operate best.
These products fall into 2 categories. The first sort of devices already has wireless built in. Second-category products, such as some streaming audio products, have optional wireless capability. Typically they have a slot to add a wireless LAN card. Recent touch-screen iPods and iPhones already have WiFi and Bluetooth built in.
The Bluetooth protocol is a relatively low-cost solution. Yet, its drawbacks have an effect on high-quality audio applications and are often overlooked.
1) Restricted range
The range of Bluetooth devices is usually just 30 ft. This excludes Bluetooth from multi-room applications.
2) Audio compression because of restricted data rate
Bluetooth offers a maximum reliable data rate of around 1 Mbps only. This rate is not large enough to send uncompressed CD-quality audio. Therefore Bluetooth wireless devices apply audio compression. This is less critical however for compressed audio such as MP3 audio but excludes Bluetooth from use in high-quality audio applications.
3) Audio delay
The signal sent via Bluetooth will undergo a slight delay of no less than 10 ms. This is mostly because of the audio compression. While being uncritical for MP3 players, this delay may be a problem for video and other real-time applications.
4) No support of multiple headphones
Bluetooth is relatively restricted regarding supporting streaming to numerous headphones. Streaming to numerous headphones is helpful for several people wanting to listen to the same transmitter. This is less of a problem for MP3 player applications.
Another widespread protocol is WiFi which supports uncompressed audio but also has limitations simultaneously streaming to multiple receivers. As a result of the relatively high power consumption it is rarely utilized in wireless headphones though. WiFi is convenient for streaming audio from a PC however because nearly all PCs have WiFi access.
While newest-generation wireless speakers and wireless amplifier products employ proprietary digital technologies, low-cost devices regularly still rely on FM transmission which is noisy and has high audio degradation and high susceptibility to radio interference.
Modern wireless audio protocols avoid audio degradation by employing digital transmission. These often also come with mechanisms including forward error correction to deal with interference from other wireless devices.
Latest-generation wireless amplifiers utilize uncompressed audio transmission. Latest protocols also allow streaming to an infinite number of receivers. This allows 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. Wireless audio transmitters typically work at 2.4 GHz or sometimes in the less crowded 5.8 GHz frequency band including Amphony’s wireless audio products.
These wireless amplifiers also differ regarding amplifier output power, standby power consumption and audio quality. A high-quality audio amplifier is critical for optimum sound quality. Wireless Class-D amplifiers generally have standby power of 5 Watts or less and a power efficiency of greater than 80% but sometimes high audio distortion. It is important to choose a wireless amplifier with low audio distortion. This will make sure good sound quality. High-quality amplifiers have audio distortion of 0.05% or less.