leema-acoustics Monoblock Power Amp User manual

Preliminary Handbook
Leema Acoustics Elements Stereo / Monoblock Power Amp
Leema Electro Acoustics Limited
Unit K, Henfaes Lane, Welshpool, Powys, SY21 7BE, UK
Tel/Fax: [phone] email: [e-mail] web: www.leema-acoustics.com

Index
EC Declaration of Conformity ................................................. 3
Introduction ................................................................. 4
Safety Advice ................................................................ 5
Elements Power Amplifier overview ............................................ 5
Environmental, Made in the UK, Contact Us .................................... 5
Rear Panel Connections & Switches ............................................ 6
Channel Switch, Mode Switch, LIPS ............................................ 6
RCA/XLR, NORM/MONO ........................................................... 6
Loudspeaker Outputs .......................................................... 6
Preamp Output ................................................................ 7
LIPS Connection .............................................................. 7
Loudspeaker Terminals ........................................................ 7
Cables ....................................................................... 7
Power Switch ................................................................. 7
LIPS Volume Control .......................................................... 7
What is LIPS? ................................................................ 8
LIPS Specifics ............................................................... 8
LIPS Packets ................................................................. 8
LIPS Codes ................................................................... 8
Audio Specifications ......................................................... 8
WEEE Scheme .................................................................. 8
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EC Declaration of Conformity
In accordance with EN ISO 17070-1:2004
We Leema Electro Acoustics Limited
of Welshpool
Powys
UK
in accordance with the following Directive(s):
2006/95/EC The Low Voltage Directive
2004/108/EC The Electromagnetic Compatibility Directive
hereby declare that: Equipment Hi-Fi Power Amplifier Model Name:
ELEMENTS STEREO / MONOBLOCK Power Amp
is in conformity with the applicable requirements of the following standards:
Standard. No. Name International Equivalents
BS EN60065; 2002 Electrical Safety Requirements EN60065; 2002 / IEC60065; 2001
BS EN 55020; 2002 EMC Immunity EN55020; 2002 / CISPR 20; 2002
BS EN 55013; 2001 EMC Emissions EN55013; 2001 / CISPR 12; 2001
BS EN 61000-3-2; 2001 EMC Limits for Harmonic Emissions EN61000-3-2; 2000 / IEC61000-3-2; 2000
BS EN 61000-3-3; 1995 EMC Limits for Voltage Fluctuations EN61000-3-3; 1995 / IEC61000-3-3; 1994
I hereby declare that the equipment named above has been designed to comply with the relevant sections of
the above referenced specifications. The unit complies with all applicable Essential Requirements of the
Directives and Standards.
Signed by: .................................................................................................................................................
Name: Mallory Nicholls
Position: Technical Director
Done at: Leema Electro Acoustics Ltd.
On: 26/4/2013
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Introduction
Congratulations on your purchase of a Leema Elements Stereo / Monoblock Power Amplifier.
The Leema range of products has been painstakingly engineered in the United Kingdom to offer genuine
state-of-the-art performance.
Partnered with suitable equipment, Leema amplification will provide audio performance far beyond that of
competitors and will equal or better the performance of products costing many times their purchase price.
A notable feature of all Leema amplification is incredible bass power and control, due to massive current
capability, together with superb clarity and finesse in the upper frequencies with stunning realism in the
midband.
Purchasers should read and follow this instruction manual, paying particular attention to the user installation
and safety advice section.
This manual has been written to enable you to achieve the very best performance and maximum listening
pleasure from your investment.
We wish you many years of pleasurable listening... Move Your World!
With best regards
The Leema Team.
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VERY IMPORTANT
Before connecting your new Leema amplifier to the rest of your system, please ensure that the loudspeaker
cables are correctly and firmly attached to the 4mm banana sockets on the rear of the unit. All required
sources should also be connected BEFORE inserting the mains power lead and powering for the first time.
Although the amplifier has short-circuit protection, shorts should be avoided to reduce the stress on the
amplifier.
User installation and safety advice
Please ensure that the mains voltage of your new amplifier is correct for your region. The setting is displayed
on a label above the mains power inlet. The mains voltage setting is not user adjustable, therefore the
amplifier must be returned to the manufacturer if any changes are required.
Ensure the mains supply is switched off at the wall socket, or unplugged before installing or moving the
amplifier.
Do not use near water, for example do not place a potted plant on top of the unit or allow drinks to be placed
near the unit. If liquid is spilt in to the cabinet, remove the mains lead from the wall immediately. The amplifier
should then be returned to your dealer for safety testing before re-use. Failure to do so may result in electric
shock or even fire! Do not use the amplifier in damp conditions, e.g. outside of the house.
Keep away from direct sunlight and other heat sources and ensure adequate ventilation around the amplifier
to maintain proper cooling. Units MUST NOT be stacked directly on top of each other.
Never attempt to open the cabinet. There are no user adjustable parts inside and doing so will invalidate the
amplifier’s warranty.
In the event of an electrical storm, remove the mains power lead from the wall outlet.
Overview
As with all high-powered amplifiers, high voltages can occur at the loudspeaker sockets. Connection should
only be carried out with the unit switched off. Neither of the Black negative connectors are Earth. 4 mm
banana type plugs must be used.
Elements Stereo / Monoblock Power Amp overview
The Leema Elements Power Amplifier is a high power output, microprocessor controlled, stereo and
monoblock amplifier. It is capable of class-leading performance at the heart of an audiophile stereo system,
but thanks to the LIPS (Leema intelligent protocol system) interface, it can also be part of a stunning home
cinema or surround music system. Each component in the system dynamically configures in real time
depending on the requirements of each input source. The microprocessor gives an unprecedented degree of
sophistication, making Leema products easy to use for all the family.
Environmental Issues
Leema operates a 100% recycling program. All waste materials generated as part of the manufacturing
process are recycled via a licensed specialist company. The power drain from all Leema electronics, in
standby or power off modes, has been optimised to a negligible level. All Leema amplifiers have been
designed to attain full operational specifications and sound quality within a few minutes of switch-on.
Made in the UK
Leema electronics are designed and manufactured in the UK.
Contact Us
Leema may be contacted via our website: www.leema-acoustics.com or by telephone: [phone]
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Rear Panel Connections & Switches
Channel Switch
Because the amplifier can be used under LIPS control, where the volume level is controlled inside the power
amplifier, the unit needs to understand how it is being used. The channel switch tells the unit if it being used
in normal stereo mode, or as a monoblock feeding the right or left speaker. Set this switch appropriately to
enable the amplifier to respond to LIPS control messages correctly.
Mode Switch
The mode switch allows the gain of the amplifier to be reduced by 6dB when set to 'mono'. This setting may
be used when the amplifier is configured for monoblock operation (which would normally increase the gain
by 6dB) but the gain increase is undesirable, for example, when mixing stereo and monoblock amplifiers in
the same system with monoblocks driving the woofers and a stereo amplifier driving the tweeters. In this
case setting the mode switch to mono will make the monoblock gain match other stereo amplifiers in the
system.
LIPS
The LIPS switch offers three modes of operation:
LIPS VAR(iable) – In this mode, the input is locked to the SLAVE/AV input, but the volume is controlled by
LIPS data. Use this mode when using the amplifier with a LIPS capable Pre-amp, Pyxis for example. In this
case, Pyxis would be set to fixed output (LIPS mode) and the system volume would be controlled inside the
power amps via a LIPS connection.
FIXED – In this mode, the amplifier behaves like a conventional power amp with fixed volume level. The
input is via SLAVE/AV.
SURROUND – In this mode, the volume level is controlled via LIPS as in LIPS VAR mode, but the input can
be selected via LIPS between SLAVE/AV and Multi 1 for use in surround systems.
RCA/XLR
This is a pushbutton which is located behind the rear panel so that it cannot be pushed accidentally. The
switch sets the SLAVE/AV input to the XLR or RCA connectors. With the power removed, use a small object
such as a cocktail stick, to gently push or release the switch.
NORM/MONO
This is a pushbutton which is located behind the rear panel so that it cannot be pushed accidentally. The
switch selects between Normal stereo operation and Monoblock mode. With the power removed, use a small
object such as a cocktail stick, to gently push or release the switch.
Loudspeaker Outputs
The loudspeakers connect here. Ensure correct polarity:
Red terminal is +
Black terminal is -
WARNING
Black terminals are NOT grounded.
Do not make connections with unit connected to the mains supply.
4mm banana type plugs must be used.
Note: To use Monoblock mode, the speaker cables must be connected differently to stereo mode. Refer to
the rear panel legend for connection details.
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Preamp Output
Outputs are provided which mirror the selected input e.g. SLAVE/AV or Multi 1. These outputs are controlled
by the amplifier's volume control and can be used for a variety of uses. Examples include feeding an
amplifier in another room for a simple multi-room system, or as a line level feed to a subwoofer. They can
also be used for bi-amping, where one amplifier is used to drive the tweeters in the loudspeakers and a
second is used to drive the woofers.
Bi-amping offers an increase in clarity by reducing intermodulation distortion. The loudspeaker no longer
draws bass current from the amplifier feeding the tweeter, resulting in cleaner high-frequencies etc. The
loudspeakers must be suitable for bi-amping, this is normally the case where there are two pairs of binding
post connections available on the rear of the loudspeaker cabinets. When bi-amping, it is VITAL to remove
the bridging links from the connection panel on the rear of the speakers, otherwise the outputs of the two
stereo amplifiers will be connected together, which will result in considerable damage.
If you are considering bi-amping and are unsure, please contact your dealer or Leema Electro Acoustics Ltd.
for advice.
LIPS Connection
LIPS cables are directional and have one black end and one red. If the amplifier is controlling other units, the
black connector should be plugged in to either LIPS socket and the red connector plugged in to the next
component. If the amplifier is to be controlled, the black connector is connected to the master device and the
red connector is plugged in to either LIPS socket on the rear of the power amplifier.
Loudspeaker Terminals
There are two pairs of low profile loudspeaker terminals on the rear panel, one pair for the left loudspeaker
and one pair for the right loudspeaker. They are designed for industry standard 4mm banana type plugs.
They are not suitable for bare wire connection. Due to the amplifier's unique circuit topology, neither of the
Black sockets are earthed.
Cables
Never underestimate the importance of good quality speaker cables, bell wire or lighting flex will simply not
do. The higher the system resolution, the more easily the differences between cables can be discerned.
Leema recommend the use of high quality bi-wire cables with your new amplifier to ensure optimum fidelity.
However, a single high quality run is always superior to two runs of inferior cable. If your budget is tight, get
the best quality single run you can afford. Leema recommend Leema Linx cables for optimum system
synergy.
Power Switch
The Power button toggles the amplifier between Power On and Off. If a LIPS connection is used, the power
status can be controlled and any other Leema components connected via LIPS will also be controlled.
LIPS Volume Control
The volume is adjusted via a precision attenuator under microprocessor control. This method of volume
control permanently ensures the highest fidelity without the gradual degeneration of conventional motorised
volume controls. It also allows the volume of multiple amplifier to be synchronised. The volume control also
regulates the pre-out volume.
Note: Small clicks in the audio during volume changes are normal.
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What is LIPS?
LIPS or Leema Intelligent Protocol System, facilitates communication between various items in a Leema
audio system. It allows units such as the Elements Integrated and Tucana II, to control other items in a chain.
Leema’s 5.2 surround system is a good example, where an Elements Integrated controls multiple Elements
Power amplifiers and Essentials Volume modules for subwoofer level control. Key information including
volume level, input selection and power control is passed through the bus enabling other units to operate in
synchronisation. Intelligence is added within each receiving unit, for example, a power amplifier handling the
surround channels of a surround system ‘knows’ that it won’t be required when listening to a stereo source
such as CD. Therefore, when the Elements power amplifier ‘sees’ the CD input, it powers itself down.
Each Leema unit can be controlled via the LIPS bus. Controlling units externally for example, enables them
to be used within a home automation system.
LIPS Specifics
The LIPS bus is driven by an open-drain output. Leema can supply a full RS232 interface if required. The
communication standard follows the common RS232 format of No Parity, 8 data bits and 1 stop bit. The baud
rate is 38400.
LIPS Packets
Each communication on the LIPS bus contains a packet of four data bytes as follows:
First a header is sent with a value of 255. This alerts the receivers to incoming data.
Next, a command header is sent. For a volume command, this would be 40.
Next, a value relating to the command is sent. For volume this would be 0 to 248.
Finally a tail byte is sent with a value of 0.
LIPS codes
For further information, please contact Leema Technical Support.
Audio Specifications
Power Output Stereo Mode:
8 Ohms: 55 Watts RMS per channel, 4 Ohms: 92 Watts RMS per channel, 2 Ohms: 160 Watts RMS per channel
Minimum load impedance: 2 ohms
Power Output Monoblock Mode:
8 Ohms: 210 Watts, 4 Ohms: 365 Watts RMS
Minimum load impedance: 4 ohms
Output Current: greater than +/- 12 Amps
Frequency response +0/-3dB @ 1W: 5Hz - 80KHz
Noise (A weighted, volume control minimum): -105dBm
Signal to Noise ratio (A weighted, ref: 150 Watts RMS 4 ohms): -110dB
THD (10 Watts RMS 8 ohms, 1KHz): 0.015% (Measured AES 17)
Maximum DC offset: +/- 50mV
Specifications subject to change without notice.
WEEE Scheme
Disposal of Electronic Equipment in the European Union and other countries with collection procedures:
The wheelie bin symbol on this product indicates that it shall not be treated as household waste. It should be disposed of
via a collection point for the recycling of electrical and electronic equipment.
Leema is fully registered under WEEE/HK 0757 ZX
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