Wireless Geekz

Lately more and more wireless audio transmitter devices have emerged which claim to bring the ultimate freedom of broadcasting music throughout the house. We will have a look at different products and technologies to find out in how far these devices are effective for whole-house audio uses and what to look out for when buying a wireless system.

If your home is not wired for audio then you face quite a problem when you want to get your music from your living room to your bedroom. Frequently the audio source cannot be moved. Running speaker wires between rooms will be expensive and for that reason a lot of people are searching for alternatives. There are several technologies solving this problem. These include infrared wireless, RF wireless, wireless LAN (WLAN) and powerline.

Infrared products broadcast the audio as lightwaves. Light cannot penetrate walls. As a result devices utilizing infrared, such as wireless surround sound kits, are restricted to a single room.

RF wireless products send the audio as RF waves – either by using FM transmission or digital transmission – and can for that reason easily transmit through walls. The least expensive option is FM transmission. Products using FM transmission, on the other hand, have a number of drawbacks. These include degradation of the audio quality due to noise or hiss and audio distortion. In addition, FM transmitter products are also rather susceptible to interference from other wireless transmitters.

Products which employ digital wireless audio transmission employ a digital protocol. Such devices include transmitters from Amphony. In this protocol, before transmission the audio signal is converted to digital data. This method guarantees that the audio quality is entirely maintained. Some transmitters use some sort 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 since wireless LAN was not originally designed for real-time audio streaming. Also, a number of products require to buy separate wireless LAN modules that are plugged into every audio receiver.

Powerline products broadcast the audio via the power mains and offer large range. They run into problems in houses 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 selecting a wireless audio system: If you plan to stream audio into numerous rooms of your house, be sure to pick a system that allows streaming to several receivers at the same time. That way you don’t have to buy a separate transmitter for each receiver that you are streaming to. Picking a product with some type of error correction will help mitigate against strong RF interference. Such interference can be brought on by other wireless transmitters. Select a digital RF audio transmitter to ensure that the audio quality is preserved. Make sure the audio latency is less than 10 ms if you have a real-time application such as video.

Select a transmitter that has all the audio inputs you need, such as speaker inputs, line-level RCA inputs etc. Select a system where you can add receivers later on which provide all of the required outputs, e.g. amplified speaker outputs, RCA outputs etc. If you go with a digital audio transmitter, choose one with an input audio level control knob to avoid the music signal from clipping inside the transmitter audio converter. This will guarantee optimum dynamic range regardless of the signal level of your equipment.

Ensure that the system offers 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. Select a system which offers receivers that can drive speakers with the desired Ohm rating. Make sure the receivers have a small form factor and are easily mountable. This will help during the set up. Devices utilizing the less crowded 5.8 GHz frequency band will generally have less trouble with wireless interference than 900 MHz or 2.4 GHz devices.