| An increasing number of wireless audio | | | | problems in houses where there are separate |
| transmitter products promise the ultimate | | | | mains circuits in terms of being able to cross over |
| freedom in streaming music all over the house. | | | | into another circuit. Also, these products build in a |
| We will take a look at different products and | | | | delay of several seconds to safeguard against |
| technologies to find out in how far these products | | | | transmission errors during power surges and |
| are useful for whole-house audio applications and | | | | spikes which prevents their use in applications |
| what to look out for when buying a wireless | | | | where the audio from wireless speakers has to |
| system. | | | | be in sync with other non-wireless speakers or |
| Running music in your house can be a daunting | | | | video. |
| task. Many homes are not wired for multi-room | | | | Here are some tips for picking a wireless audio |
| audio and getting the music from your living room | | | | system: If you plan to stream audio into several |
| to your bedroom can be quite a challenge. | | | | rooms of your house, be sure to select a system |
| Products which solve this problem are usually | | | | that allows streaming to multiple receivers at the |
| based on the following technologies: infrared | | | | same time. That way you don't have to buy a |
| wireless, RF wireless, wireless LAN or powerline. | | | | separate transmitter for each receiver that you |
| Infrared wireless audio products are limited to | | | | are streaming to. Some products have some |
| line-of-sight applications, i.e. only operate within a | | | | form of error correction built in which will help |
| single room since the signal is sent as infrared light | | | | guard against dropouts in case of strong wireless |
| which cannot penetrate walls. This technology is | | | | interference. Pick a digital RF audio transmitter to |
| often found in wireless speaker kit products. | | | | ensure that the audio quality is preserved. Make |
| RF wireless audio products send the audio signal | | | | sure the audio latency is less than 10 ms if you |
| via radio waves. These radio wave signals can | | | | have a real-time application such as video. |
| easily go through walls. The signal is sent either by | | | | Select a transmitter that has all of the audio |
| using FM transmission or digital transmission. FM | | | | inputs you need, e.g. speaker inputs, RCA inputs |
| transmitters are the least expensive option. They | | | | etc. Choose a system where you can add |
| offer good range but the audio signal is prone to | | | | receivers later on which offer all of the required |
| audio distortion and noise and is very susceptible | | | | outputs, e.g. amplified speaker outputs, RCA |
| to interference from other wireless transmitters. | | | | outputs etc. If you go with a digital audio |
| Digital wireless audio transmitter products utilize a | | | | transmitter, choose one with an input audio level |
| digital protocol. The audio is first converted to | | | | control knob to prevent the audio signal from |
| digital data before being transmitted. This method | | | | clipping inside the transmitter audio converter. This |
| ensures that the audio quality is fully preserved. | | | | will ensure optimum dynamic range regardless of |
| Some transmitters use some form of audio | | | | the signal level of your equipment. |
| compression, such as Bluetooth transmitters, | | | | Check that the amplified wireless receivers have |
| which will degrade the audio to some degree. | | | | built-in digital amplifiers with low distortion figures. |
| Transmitters which send the audio data | | | | This will keep the receiver cool due to high |
| uncompressed will achieve the highest fidelity. | | | | amplifier power efficiency and provide optimum |
| Products using wireless LAN are useful when | | | | sound quality. Make sure the receivers can drive |
| streaming audio from a PC. Their drawback is | | | | speakers with your desired Ohm rating. Picking a |
| that they typically have some fairly high latency, | | | | product where the wireless receivers have a small |
| i.e. the signal will be delayed by some amount | | | | footprint and easy mounting options will help |
| since wireless LAN was not specifically designed | | | | during the installation. Products which operate in |
| for real-time audio streaming. Also, some products | | | | the 5.8 GHz frequency band will have less |
| require to purchase separate wireless LAN | | | | problems with wireless interference than products |
| modules that are plugged into each audio receiver. | | | | using the crowded 900 MHz or 2.4 GHz frequency |
| Powerline products send the audio via the power | | | | band. |
| mains and offer great range. They run into | | | | |