- Enjoyable sound reproduction.
The most important thing about any audio system is how much you enjoy listening to it. If
your audio system is not nice to listen to, then nothing else makes up for this - not the
manufacturers big brand name, nor the snazzy displays, futuristic remote controls, swish
cabinets, trendy small speakers, or how many songs you can store on it.
When you are building or renovating, you usually only have one
chance to get your audio system right, because after the plaster goes on it can be
impractical to change your cabling to support the sound system that you should have
installed. Good multi-room audio requires careful consultation with you, audio engineering
knowledge and experience, and your involvement.
- Make good use of your best sounding audio source.
Your music can sound no better than it does as it comes from your audio source. Every
amplifier, cable and speaker that follows cannot improve on the audio source. A defining
feature of multi-room
audio is that remote rooms may listen to a shared "main room" audio
source, so this audio source sets the upper limit on how good your entire multi-room
audio hi-fi system sounds.
It makes sense to use the highest quality source in your home theatre
(or listening room) also as the main room source for your multi-room
audio, as it will usually sound much better than the audio source included in
most multi-room audio components.
- Use quality local room amplifiers and short speaker cables.
Ensure that your multi-room audio hi-fi uses
distributed room amplifiers, such as C-Bus room
amps or Niles room amps,
located close to quality in-ceiling speakers, such as Niles CM860
or Krix Atmospherix ceiling
speakers, in each room to minimise speaker cable lengths. By minimising the
impedance between each hi-fi room amplifier and your room speakers in this way, each room
amplifier may better control its speakers to produce better quality sound.
Relatively large currents flow through speaker cables, so that
even small increases in speaker cable resistance or impedance adversely affect
reproduction quality. If you mistakenly use one centrally located multi-channel audio
amplifier with long speaker cables radiating out to all your remote room speakers, you
will usually increase speaker cable impedance and substantially reduce the quality of
sound from your multi-room speakers.
Speaker cables also act like antennas, picking up unwanted EMI
and noise and injecting it into your multi-room audio hi-fi system. This unwanted noise
audibly degrades sound quality further. The shorter you keep your speaker cables, and the
further you keep them from sources of electromagnetic noise, the better your multi-room
system will sound.
- Use pre-power-amp volume controls.
Every volume control in your multi-room audio hi-fi system
should be implemented before the multi-room
amplifiers and not after them along the speaker cables. Any self-respecting
audio system implements volume control between the preamp and poweramp where currents are
very low, and multi-room audio hi-fi systems should be no different.
Many poorly designed multi-room audio systems take the low-cost
approach of installing inefficient analog rheostats/potentiometers (those round volume
knobs) on wall plates inside each remote room, to reduce the volume reaching the speakers
through the speaker cables. This inserts a large impedance (that of the wall volume
control) between the amplifier and the speaker, making it impossible for the
amplifier to accurately control and drive the speaker. In other words, it makes your
multi-room system sound awful!
Using pre-power-amplifier volume controls requires that:
(a) The room amplifier be accessible inside the room and have a volume control on its
front panel, or
(b) A special wall mounted wired remote control panel must be installed and wired to a
hidden multi-room room amplifier. Even though the multi-room control panel may itself seem
to be the whole volume control, allowing you to see and change the volume level, it
actually controls the pre-power-amp volume control located inside the room amplifier.
- Use quality loudspeakers.
Nearly everyone knows that speakers vary widely in the quality of the sound they can
reproduce, and that you should select the highest quality speakers that are appropriate
for the room and application. This remains true in a multi-room audio hi-fi system.
So what do we mean by "quality loudspeakers" for example?
For high quality in-wall
speakers, in-ceiling
speakers, or outside speakers it
is difficult to go past the extensive range of Krix speakers
or Niles speakers.
- Use the best sounding speaker type appropriate for each room.
Loudspeaker types include free-standing floor speaker, bookshelf speaker, on-wall,
in-wall, or in ceiling loudspeaker. Loudspeakers depend heavily upon the quality of their
cabinets to perform well. A free-standing floor speaker's ability to produce enjoyable
music depends more on the quality of its own cabinet and less upon the acoustic properties
of the room in which it is placed, because of its relative isolation from the floor, walls
and ceiling. In contrast, an in-wall (or in-ceiling) speaker's performance is strongly
affected by the construction of the immediate wall cavity that often forms the in-wall
speaker's speaker box, and also how well the plaster is braced around the speaker.
Since quality loudspeaker boxes are built with better acoustic
properties than the rooms in which they are placed, you may list loudspeaker types in
order of sound quality as follows, from best sounding to worst:
1. Floor standing speakers,
sitting at least 1m from any wall (best sound quality).
2. Bookshelf speakers, with
care to leave sufficient space behind and around them and a rigid shelf.
3. On-wall speakers, which have
their own enclosure but are mounted with brackets on the wall surface.
4. In-wall speakers,
mounted at ear height with care taken to seal in-wall cavities and brace the plaster.
5. In-ceiling speakers,
which are worst of all because the dispersion pattern from the ceiling is usually least
ideal, and ceilings are usually less rigid than walls.
As sound quality decreases in the above order, so too does
aesthetic impact, with in-ceiling speakers being the most inconspicuous. You can even
obtain Krix
Holographix downlight size speakers for mimimal aesthetic impact. Good
multi-room audio hi-fi system design usually involves reaching a different
performance/aesthetic trade-off that is appropriate for each room.
- Carefully consider loudspeaker locations.
Loudspeakers also need to be carefully located to get the most from them. Location affects
frequency response, stereo imaging (how well soundstage is recreated for you) and how
evenly they disperse music throughout your room.
Your Clever Home engineer
will be able to advise you on the best speaker locations, while taking into account the
other restrictions and priorities associated with you home, as part of your Clever Home
automation project proposal.
- Install a wired multi-room audio hi-fi system.
Use hardwired connections between all audio components for higher quality and more
reliable communications and audio transmission. Wireless is a great option to have when
you cannot install any cabling, and you are prepared to accept audio dropouts and reduced
sound quality. However, unless you need mobile room speakers, a wired multi-room
audio system is a much better option when access is available to install
wiring. Marketing hype for wireless convenience tends to be at odds with practicality when
it comes to multi-room audio hi-fi.
- Seek Engineering standard support.
A home multi-room audio (hi-fi or not) is a significant long term investment. You deserve
and require better advice and guidance than a shop salesperson or an electrician is able
to provide. It is up to you to seek out genuine engineering-standard
support from a custom installer with the knowledge and experience to help you.
- Select a suitable multi-room audio user interface.
A multi-room
audio system should allow you to change the volume, and monitor and control
the shared audio source from within each remote room. This means that you will require a
multi-room audio user interface, with which to see and change the current radio stations
or music track, or to stop, pause, or fast forward/rewind, for example.
While hi-tech wireless touch screen controls create a great
impression, you have to ask yourself:
(a) How many of these expensive wireless remote controls do you need?
(b) How do you plan to keep track of where they have been left?
(c) What schedule to you plan to implement to keep their batteries recharged?
(d) How can you prevent these expensive wireless touch screen controls from being dropped,
damaged, or even stolen?
A more practical option is usually to installed fixed wall
mounted multi-room control panels in each remote room. These control panels may be audio
system specific, or they may be part of an integrated home automation system. If a hard
disk based music library is also involved, then any computer on your wired or wireless
home network running appropriate software becomes another potential multi-room audio user
interface.
- Ensure your multi-room audio hi-fi is expandable.
You should not only support the number of room
amplifiers and multi-room loudspeakers,
shared and local audio sources, that you need initially. You should also plan further
ahead and cater for the possible addition of extra rooms or sources, or an upgrades to
more powerful or higher quality Niles power
amplifiers or other audio equipment.
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