Crucially, the way the speakers perform also varies according to where they are located in the room. While in-ceiling speakers have less diffraction than a box speaker, which can result in improved mid and high frequency reproduction, some of these benefits can be negated by vibrations in the wall.
If possible you should try to visit custom installers' demonstration rooms where ceiling speakers are in place in order to get some idea of how they might sound. Owners of flats should also check to see if they are allowed to install speakers in the walls or ceiling.
One problem, especially if you are trying to put a speaker in a party wall, is that it can reduce the fire retardant properties of any insulation provided which can invalidate the insurance.
Entry level systems
Choosing the type of speaker you want isn't the only decision you'll have to make when putting together an audio setup. Questions you should ask yourself are: "How many rooms do I want to listen to music in?" and, "How many sources do I want to control?" If you only want to listen to two sources in two rooms, then you will need only a very basic system.
One system definitely worth considering is the QED MusiQ (www.qed.co.uk/multiroom). One MusiQ controller covers two additional rooms to the one your hi-fi is in, and drives them independently via four channels of built-in power amplification.
Not only can you listen to two sources in two different rooms at the same time, it's also possible to adjust volumes independently. Control of your CD player and tuner is provided via basic, but easy to use, in-wall controls.
The keypads also feature infrared control relay so you can, say, flick between digital radio stations on your Sky box.
Another company worth considering is Opus (www.opus-technologies.co.uk). It offers two systems: the Octopus (from around £1,300) and the Opus 500 (from around £4,700).
Designed as a DIY solution, the Octopus system is based on A-BUS technology which uses cheap Cat-5 cable for providing audio control. Provided is the WCU310 wall control unit, comprising controls for each room, an infrared receiver and a 15W amplifier to power the ceiling speakers.
There's also a master control unit that can distribute audio signals to four zones and four sub-zones (a sub-zone is an area like an en suite bathroom which reproduces the same audio from the adjoining bedroom).
More advanced is the Opus 500. Like the Octopus, it's capable of controlling six music sources across four zones and four sub-zones. However, it comes with a more advanced wall panel that displays information such as equipment status and volume up/down.
Master and server
With audio servers becoming increasingly popular, many manufacturers are combining hard drive-based products and multiroom functionality.
As mentioned earlier, Imerge offers wired/wireless network media players to extend the use of its sound servers to additional rooms, while Living Control (www.livingcontrol.com) provides a multiroom solution based around its latest Afinity Series MusicBox 3 digital server.
Featuring a 160GB hard drive that's capable of storing 2,650 hours of music, the MusicBox can stream three sources of music at the same time and is designed to interface with the company's RoomBox4 (four zone) and RoomBox6 (six zone) multiroom systems.
Control is provided by in-wall DisplayPads available in a number of different designs, while the company is working on a Netbox wireless interface that will enable you to use a PDA or webpad either in addition or instead of the wall pads.
Linn (www.linn.co.uk) also now combines a high-end audio server with its multiroom audio distribution system. Able to store 2,760 hours of uncompressed audio, the well-specified Kivor sound server can be combined with the Knekt system for a complete multiroom setup.