Acoustic Energy Loudspeaker Linear Centre User Manual

							O W N E R ’ S   M A N U A L
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							Page Section
1 1 Introduction
1 2 Handling
1 3 Installation
2 4 Positioning
3 5 Connecting
4 6 Amplifiers
4 7 Listening
4 8 Specification
5 9 The Linear Range
5 10 Warranty
5 11 Contact Acoustic Energy
1 .   I n t r o d u c t i o nC o n t e n t s
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1 .   I n t r o d u c t i o n
2 .   H a n d l i n g
Welcome to the Linear Centre. Perhaps more than 
any other hi-fi product, speakers are sensitive to 
installation so please take a little time to read 
this manual and to follow, as far as practical, 
the installation guidelines it contains. Careful 
installation will help ensure that your Linear Centre 
performs optimally. Should you have any questions 
not covered here we are happy to try and answer 
them either by telephone or email. Contact 
information can be found in Section 11.
Following this introduction, the Manual is divided 
into sections covering handling, installation, 
positioning, amplifier compatibility, connection, 
listening, matching products, specifications, 
warranty and contact information. We recommend 
that you read at least the first five of these sections 
carefully before installing and using your Linear 
Centre.
The Linear Centre is a relatively delicate precision engineered product that 
can be damaged by inappropriate handling. Please take care when unpacking 
or moving the speaker not to touch any of the drivers. Damage to a driver 
will at best degrade a Linear Centre’s performance and at worst result in its 
complete failure.
The enclosure surfaces should also be handled sympathetically. Any cleaning 
should only require a soft cloth, slightly dampened if necessary. Be wary of 
using any polishes or solvent based cleaning agents.
The packaging should be retained for future use.
3 .   I n s t a l l a t i o n
The Linear Centre is intended to be used in a home theatre system located 
either directly above or below the screen. It can be stood either directly on 
a furniture unit, integrated within a screen stand, mounted on a dedicated 
speaker stand or on a wall using appropriate bracket hardware. 
Best results are likely to be gained if the Linear Centre is directly coupled 
to the floor via a dedicated, spiked stand. If the screen stand is to carry the 
Linear Centre it is advisable to de-couple it from the screen with the supplied 
adhesive rubber feet so that its does not disturb the picture. If a wall bracket 
is to be used it should be as rigid as possible and firmly attached to a brick-
built wall.
The Linear Centre is magnetically shielded. However, the extreme sensitivity 
of some CRT tubes to low levels of magnetic flux may mean that, in rare 
cases, the shielding may not be sufficient. Should your screen suffer picture 
distortion caused by the proximity of a centre speaker contact your dealer 
installer or Acoustic Energy for advice.
The following section provides further general advice on Home Theatre 
speaker positioning and room layout.
C o n t e n t s
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4 .   P o s i t i o n i n g5 .   C o n n e c t i n g
The position of the speakers in a home theatre installation will have great 
influence over its performance. It is worth spending some time experimenting 
both with the finer points of speaker positioning, as well as the larger scale 
issues of room layout. Diagram One illustrates an idealised general home 
theatre speaker layout.
If you are already familiar with the characteristics of your home theatre room, 
and the way speakers perform in it, you may already have a good feel for 
where to position your Linear Centre. However, installing any new speaker 
component provides a good opportunity to review an existing set-up and 
perhaps make improvements.
The position requirements for a Linear Centre are as follows:
•    Between 0.05 and 0.5 metres from the rear wall.
•    Generally in-line with the display screen. 
•    Directly above or below the display screen.
D i a g r a m   O n e
Don’t worry if, thanks to the architecture or layout 
of your room, it is not practical to follow each 
requirement or the layout diagram exactly. The 
most important thing is to experiment with the 
different options that are practical and find the one 
that works best.
Once your Linear Centre is connected (see Section 
5) and working, and you begin to become familiar 
with its performance, it is likely to be worthwhile 
experimenting a little more with its positioning. 
For example, reducing the distance between the 
speaker and the rear wall will increase the level of 
bass and low midrange making the speaker sound 
warmer. The warmth however is likely to be gained 
at the expense of some mid-range clarity.
LeftFront
Viewing/listening position
RightFrontCentre
LeftSurroundRightSurround
Alternative or Extra LeftSurround
Alternative or Extra RightSurround
Sub-woofer
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4 .   P o s i t i o n i n g5 .   C o n n e c t i n g
Connecting your Linear Centre to an amplifier is 
fundamentally a simple process, however, there are 
some choices to be made and issues to consider 
concerning connection mode, connectors and 
cable type.
Linear Centre is fitted with two pairs of binding-
post terminals - one pair each for the low 
frequency and high frequency drivers. Two 
pairs of terminals enables Linear Centre to be 
connected conventionally (single wire), bi-
wired or bi-amplified. As supplied, the high and 
low frequency terminals are connected together 
by metal shorting links ready for conventional 
connection.
The terminals can accept either stripped wires, 
spade connectors, or 4mm plugs. Each of these 
termination methods is potentially equally effective 
and the choice is likely to be influenced by type of 
speaker cable used. Your dealer, distributor or cable 
manufacturer will be able to offer advice.
Conventional [single wire] connection
Conventional connection requires that the shorting links remain in place 
between the high and low frequency terminals. Simply connect the speaker 
cable to either pair of terminals ensuring correct connection polarity as 
described below.
Bi-Wire Connection
Bi-wiring separates the low and high frequency connections and can provide 
enhanced sound quality. A second set of cables (or alternatively, a multi-way 
bi-wire cable) is required. The shorting links should be removed and stored for 
any subsequent single wire use.
The two cables for each speaker should be connected in parallel to the 
amplifier terminals. At the speaker, one cable should connect to the high 
frequency terminals and one to the low frequency terminals. Ensure correct 
connection polarity as described below.
Bi-Amplifier Connection
Bi-amplifier connection adds a second power amplifier to the system so that 
high and low frequency sections have dedicated amplifiers. Significantly 
enhanced sound quality is possible. One stereo amplifier should be connected 
to the high frequency terminals of each speaker and a second stereo amplifier 
connected to the low frequency terminals. The shorting links should be 
removed and stored for any subsequent single wire use. Ensure correct 
connection polarity as described below. Follow the amplifier manufacturer’s 
guidance on connecting the amplifier input signals.
The shorting links must be removed for bi-amplifier connection. Failure 
to do so will likely result in damage to the amplifiers.
Connection Polarity
It is important when connecting speakers to ensure that each terminal is 
connected with the correct polarity. Positive speaker terminals should always 
be connected back to amplifier positive terminals, and negative speaker 
terminals connected back to amplifier negative terminals. Performance will be 
seriously degraded if connections are made with incorrect polarity.
Take care when connecting cables not to touch the negative and positive 
terminals together and “short-circuit” the amplifier. Make connections with 
the amplifier switched off.
Choice of cable type will be influenced by the characteristics of other 
components in your hi-fi system and your dealer or distributor will be able to 
advise. Even so, there are some simple guidelines to consider:
•  Cable runs to should be kept as short as possible. 
•  Short cable runs are especially important if the cable is of relatively small 
cross-sectional-area. 
•  If the cable is advertised as “directional” care should be taken to ensure 
that its orientation is as recommended.
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6 .   A m p l i f i e r s9 .   T h e   L i n e a r   R a n g e
It is wise before listening to your Linear Centre to make one final check of 
the cables and connections. If all appears well begin listening at a relatively 
low level to confirm that the system is operating as expected. Only increase 
the volume if you are happy that the sound at low levels is fundamentally as 
expected. If you are unhappy, turn the system off and re-check all the cables 
and connections.
Linear Centre may take a little time to “run-in”, and similarly the system will 
also perhaps take some time to reach normal operating temperatures. It is 
unwise therefore to make rapid judgements about the performance of the 
speaker. Your ears too will take some time to adjust to the new sound, so 
revisiting the system set-up, speaker positioning especially, is best left for a 
few days.
7 .   L i s t e n i n g8 .   S p e c i f i c a t i o n
Type: Two and a half-way, reflex loaded, time 
aligned speaker.
Bass/Mid Drivers: 2 x 130mm pressed alloy cone 
with 32mm thermally bonded voice coil. Shielded 
high-power long-throw magnet system.
HF Driver: Pre-coated textile dome with ferro-fluid 
cooled neodymium magnet system and rear heat 
sink.
Filter Network: 3rd order at 3.1kHz, 2nd order at 
275Hz
Cabinet: 15mm MDF carcass with composite layer 
front panel and driver de-coupling.
Frequency Response: 60Hz to 28kHz ±3dB 
Frequency Range: 50Hz to 28kHz @ -6dB 
Power Handling: 175W peak programme
Amplifier Compatibility: 25 - 175 Watts into 8 
Ohms 
Nominal Impedance: 8 Ohms 
Sensitivity: 91dB for 1 Watt at 1 metre
Terminals: Gold plated bi-wire binding posts
Dimensions (H x W x D): 180 x 620 x 200mm 
Weight: 10.5kg (single, unpacked)
Acoustic Energy reserves the right to modify 
product specifications.
The Linear Centre is a relatively high sensitivity speaker that does not require 
a generously rated power amplifier for adequate volume levels to be achieved 
in an average listening room. A minimum of 25 and maximum of 175 
Watts into 8 Ohms per channel is recommended. Linear Centre also offers 
a relatively easy load to the amplifier and does not make unusually heavy 
demands on its power delivery. 
No overload protection systems are fitted to the Linear Centre so it is possible 
to cause damage through over-driving. Such damage can occur whatever 
the power rating of the amplifier and is not covered by any warranty. If ever 
the sound at high volumes becomes distorted your Linear Centre is at risk of 
damage. In such circumstances the volume must be reduced.
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6 .   A m p l i f i e r s9 .   T h e   L i n e a r   R a n g e
8 .   S p e c i f i c a t i o n
1 0 .   W a r r a n t y
1 1 .   C o n t a c t
The Linear Centre is part of a range that includes 
Linear One stand-mount speaker, the Linear Three 
floor-stand speaker and the Linear Sub active 
sub-woofer. Linear One, Linear Three and Linear 
Centre incorporate time-aligned drivers to improve 
image quality, depth and focus.
Linear One
Linear One is a compact two-way stand-mount 
speaker that adds high resolution accuracy to the 
imaging benefits of time alignment.
Linear Three
Linear Three is a true three-way floor stand speaker 
that builds on the performance of the Linear One 
with wider bandwidth, higher power handling and 
enhanced detail resolution.
Linear Sub
Linear Sub is an active sub-woofer perfect for 
enhancing Linear One bass performance or 
handling the low frequency effects channel in 
Linear audio-visual systems.
Your Acoustic Energy speakers are guaranteed against original defects in 
materials, manufacture and workmanship for 3 years from the date of 
purchase.
Under this warranty Acoustic Energy agrees to repair any defect or, at the 
company’s discretion, replace the faulty component(s) without charge for 
parts or labour. This warranty does not imply any acceptance by Acoustic 
Energy or its agents for consequential loss or damage and specifically 
excludes fair wear and tear, accident, misuse or unauthorised modification.
This warranty is applicable in the United Kingdom only and does not in any 
way limit the customer’s legal rights. Claims and enquiries under the warranty 
for Acoustic Energy products purchased outside the UK should be addressed 
to the local importers or distributors. If you have reason to claim under the 
warranty please contact your dealer in the first instance.
Please retain all original packaging materials for possible future use. We 
suggest that you complete details of purchase now and keep this information 
in a safe place for future reference.
Name:
Address:
Dealer:
Purchase Date:
Serial Numbers:
Acoustic Energy Limited
16 Bridge Road
Cirencester
Gloucestershire GL7 1NJ
UK
Tel:  +44 (0)1285 654432 (Sales)
 +44 (0)1285 656890 (Technical)
Fax:  +44 (0)1285 654430
Email: [email protected]
Web:  www.acoustic-energy.co.uk
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							Acoustic Energy Limited, 16 Bridge Road, Cirencester, Gloucestershire GL7 1NJ.
Tel: +44 (0)1285 654432 (Sales), +44 (0)1285 656890 (Technical). Fax: +44 (0)1285 654430
Email: [email protected]
Web: www.acoustic-energy.co.uk
Manual Part No. MA1107
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