Acoustic Energy Loudspeaker Linear 3 User Manual

							O W N E R ’ S   M A N U A L
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							Page Section
 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
2 .   H a n d l i n g
Welcome to the Linear Three. 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 Threes 
perform 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 
Threes.
C o n t e n t s
1 .   I n t r o d u c t i o n
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2 .   H a n d l i n g
The Linear Three is a relatively delicate precision 
engineered product that can be damaged by 
inappropriate handling. It is also large and heavy. 
Please take great care therefore when unpacking 
or moving the speakers. Plan any handling in 
advance of carrying it out - ideally with a second 
person to help. Please take care when unpacking 
or moving the speakers not to touch either of the 
drivers. Damage to a driver will at best degrade a 
Linear Three’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 Three is a floor-standing loudspeaker intended to be positioned 
clear of room boundaries and coupled to the supporting floor through spikes. 
If spikes are inappropriate for your floor covering, metal protection pads, 
coins for example, maybe used between the spike and the floor.
The separately packed plinths must be attached to the bottom of each Linear 
Three before they can be installed. Invert each speaker onto a “protective” 
piece of material so as not to damage the top of the cabinet. Insert the four 
screws (supplied in the packaging) through the holes in the plinth and line 
them up with the pilot holes in the cabinet. Screw them into the cabinet 
making sure that the plinth is firmly attached. Failure firmly to attach the 
plinths will degrade the speakers’ performance.
Four M8 floor spikes and lock-nuts are supplied within the Linear Three 
packaging. The spikes and lock-nuts should be fitted to the underside of each 
Linear Three plinth once the speaker has been moved near its final location. 
Carefully lay the speaker on its back to gain access to the tapped holes in the 
plinth. Screw a spike and lock-nut into each hole leaving a length of spike 
extending beyond the lock-nut such that once the speaker is upright the 
lock-nuts will “float” just above the floor covering.
Tighten three of the lock-nuts on each speaker with a 13mm spanner leaving 
one lock-nut finger-tight to aid adjustment once the speaker is upright in its 
final position. Once the final position of each speaker has been established 
adjust the length of the loose spike such that the speaker is vertical and does 
not rock. If the floor is particularly uneven it may be necessary to loosen one 
of the tightened spikes to ensure that the speaker can be levelled.
Finally, tighten all loose lock-nuts. It may be necessary to re-adjust to 
minimise rock once the speaker has settled on the floor. Take care when 
installing floor spikes. They are sharp and can cause injury or pierce electrical 
cables.
The Linear Three can be “mass-loaded” in a compartment at the bottom of 
the cabinet. Mass loading can significantly improve the performance of the 
speaker. The compartment can be filled with washed, fully dried and non 
salt contaminated sand, or suitable metal chips, via the access hole in the 
the back panel. A plastic bung is provided to seal the cabinet. If you decide 
not to mass-load the speakers, we still recommend fitting the plastic bung 
to avoid unwanted resonance. Be aware that the plastic bung has not been 
designed to be removable after insertion. You may wish to use a temporary 
removable plug until you have made a decision whether to mass-load.
C o n t e n t s
1 .   I n t r o d u c t i o n
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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 speakers within the listening room is likely to have more 
influence over their performance than any other aspect of their installation. 
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.
If you are already familiar with the acoustic characteristics of your listening 
room, and the way speakers perform in it, you may already have a good feel 
for where to position your Linear Threes. However, installing any new hi-fi 
component provides a good opportunity to review an existing set-up and 
perhaps make improvements.
The position requirements for a pair of Linear Threes installed in an average 
sized and furnished listening room (say 4m x 5m) are as follows:
•    Between 0.5 and 1.5 metres from the rear wall.
•    1.0 metres from side walls.
•    Between 2.5 and 3.5 metres apart.
•    Clear of corners.
•     Angled inward towards the listening position.
Don’t worry if, thanks to the architecture or layout of your room, it is 
not practical to follow each requirement. The most important thing is to 
experiment with the different options that are practical and find the one that 
works best.
While it is often the first instinct to position a pair of speakers against the 
shorter wall of a rectangular room, it is often the case that a position against 
the longer wall will produce better results. This is because the long wall 
position tends to result in less prominent reflections from the side walls of the 
room. However, whether used against the long or short wall, it is important 
D i a g r a m   O n e
that each speaker of the pair is located in a similar 
acoustic environment (different environments 
would be, say, a curtained area and a solid wall). 
The acoustic character of the side walls of the room 
in the area where the main reflection between 
speakers and listening position will occur should 
also be similar. Diagram One illustrates a typical 
layout.
Once your Linear Threes are connected (see Section 
5) and working, and you begin to become familiar 
with their performance, it is likely to be worthwhile 
experimenting a little more with their positioning.
Reducing the distance between the speakers and 
the rear wall will increase the level of bass and 
low midrange making the speakers sound warmer. 
The warmth however is likely to be gained at the 
expense of some mid-range clarity and stereo image 
focus and depth. Increasing the toe-in angle of the 
speakers may regain some image focus but again 
this is likely to be at a cost of image width and 
openness. Learning through experimentation how 
Linear Threes behave in your room will help you 
find the optimum solution.
The Linear Three is magnetically shielded and can 
be used in relatively close proximity to CRT screens.
3.0 metres
angle inward
Listening position
0.5 metres from back wall  
Reflection region. Keep similar each side.
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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 Threes is fundamentally a 
simple process, however, there are some choices 
to be made and issues to consider concerning 
connection mode, connectors and cable type.
Each Linear Three 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 Threes to be 
connected conventionally (single wire), bi-wired 
or bi-amplified. As supplied, the high and low 
frequency terminals are connected together by 
metal 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 each speaker should be kept as short as possible 
consistent with each being of equal length. 
•  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 Threes 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 Threes 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 
speakers. 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: Three-way, reflex loaded, time aligned 
speaker.
Bass Driver: 160mm pressed alloy cone with 
25mm thermally bonded voice coil. Shielded high-
power long-throw magnet system. Die-cast chassis.
Mid/Bass Driver: 130mm pressed alloy cone with 
32mm thermally bonded voice coil. Shielded high-
power long-throw magnet system. Die-cast chassis.
HF Driver: Pre-coated textile dome with ferro-fluid 
cooled neodymium magnet system and rear heat 
sink.
Filter Network: 2nd order at 300Hz, 3rd order at 
3.5kHz.
Cabinet: 15mm MDF carcass with composite layer 
front panel and driver de-coupling.
Frequency Response: 40Hz to 28kHz ±3dB 
Frequency Range: 30Hz to 30kHz @ -6dB 
Power Handling: 150W peak programme
Amplifier Compatibility: 25 - 150 Watts into 8 
Ohms 
Nominal Impedance: 8 Ohms 
Sensitivity: 90.5dB for 1 Watt at 1 metre
Terminals: Gold plated, bi-wire binding posts.
Dimensions (H x W x D): 905 x 242 x 270mm 
Weight: 16kg (single, unpacked)
Acoustic Energy reserves the right to modify 
product specifications.
The Linear Three 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 150 Watts 
into 8 Ohms per channel is recommended. Linear Threes offer a relatively 
easy load to the amplifier and do not make unusually heavy demands on its 
power delivery. 
No overload protection systems are fitted to the Linear Three 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 Threes are 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
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
The Linear Three is part of a range that includes 
the Linear One stand-mount speaker, the Linear 
Centre centre channel 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 Centre
Linear Centre is a centre channel speaker designed 
to combine with the Linear One or Three for 
perfectly matched audio-visual systems.
Linear Sub
Linear Sub is an active sub-woofer perfect for 
enhancing Linear Three bass performance or 
handling the low frequency effects channel in 
Linear audio-visual systems.
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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. MA1103
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