LINEAR SOUND LTS.A220 User manual

Linear Technologie • 11 rue du Puits Rochefort • 42 100 Saint-Etienne
Tél: [phone] • Fax: [phone] • www.lineartech.fr V.2017
Please follow the instructions in this manual to obtain the optimum results from this unit.
We also recommend that you keep this manual handy for future reference.
MINI 2 CHANNELS MIXER AMPLIFIER LTS.A220
Operation manual

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1. Introduction
2. Bridge or stereo operation
3. Features
4. Front panel layout
5. Rear panel layout
6. Schematic
7. Connection / operation
8. Limiter
9. Specications
10. Precaution for use
11. Simple check and handling
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TABLE OF CONTENTS

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1. INTRODUCTION
The minimum speaker impedance for stereo (2 channel operation) is 4 ohm each. The
minimum speaker impedance for mono/bridge is 8 ohm.
If you connect and use the unit with lower speaker Impedance than what is listed above you
will damage the unit and possibly other equipment that is connected to the machine.
Do not ground the speaker output terminals. The speaker terminals may not be at ground
potential.
WARNING
Thank you for purchasing the mini mixer amplier. This unit is designed for powering
speakers in small environments. Inspection / warranty : Unpack and inspect the amplier
and its packaging. If obvious physical damage is noticed, contact the carrier immediately
to make a damages claim. We suggest saving the shipping carton and packing material for
safe transport of the unit.
To activate mono-bridge operation, press the conguration switch slide switch in the direction
as required.
2. BRIDGE OR STEREO OPERATION
• Class D high e󰀩ciency amplier
• 2 MIC / line switchable inputs : 2 unbalanced dual RCA auxiliary inputs and 2 balanced
MIC / line switchable inputs by phoenix connectors
• Input 1 and input 2 volume controls, bass and treble tone controls
• 2 channel outputs by phoenix connector, bridge or stereo output two options, with bridge
/ stereo switch
• Built-in limiter for low noise and e󰀩cient operation, with limiter on / o󰀨 switch
• DC 24 V power supply adapter is included
• Smart compact size for tabletop or wall mount design
Note : This manual assumes the user has a working knowledge of :
• Audio electronics
• Balanced and unbalanced connections
• Proper signal level setting
3. FEATURES

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5. REAR PANEL LAYOUT
6. SCHEMATIC
1. Inputs : RCA line level and balance barrier screw terminals.
2. Channel volume control : Adjusts signal level from line input to line / power and speaker
outputs.
3. Bridge / mono switch : Selects operation of stereo or mono bridge input and output
operation.
4. Limiter switch : Switches limiter circuit on or o󰀨.
1. 24V DV : For connection to power supply.
2. Speaker output : Barrier screw terminals
4. FRONT PANEL LAYOUT

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7. CONNECTION / OPERATION
8. LIMITER
The limiter is a function that prevents very loud signals from passing through it by limiting
the signal volume temporarily to a normal level. This prevents damage to the speakers or
the unit itself.
The limiter utilises a circuit that decrease the amount of very signals. It does not cut out
all potentially loud signal. Proper installation and The limiters primary function is to help
prevent one time very loud signals such as a dropping of a microphone or short loud parts
of program material.
Set up is crucial . If you are experiencing distortion, turning the limiter on may help but it is
not intended for total dynamics control.
• Connect input sources such as CD player, DVD
player or projector outputs to the unit’s inputs.
• Select bridge or stereo function.
• The unit shipped in stereo mode. To select bridge
mode, slide in the switch until it locks into position.
• Connect the outputs from the unit to your speakers.
The stereo and bridge outputs are labelled on the
speaker outputs of the unit.
• We recommend selecting the limiter on function
but the circuit may be disabled by selecting the o󰀨
position.
9. SPECIFICATIONS
Line input 775 mV /10K ohm
Speaker outputs 4 - 8 ohm
MIC input 5 mV / 600 ohm
Frequency response 50 Hz - 18 KHz (+2 dB)
Supply voltage 24 VDC
T.H.D Less than 0.1% at 1 KHz / 1/3 rated power
S/N ratio Better than 85 dB
E󰀩ciency 85%
Dimension (mm) 230 x 115 x 56
Weight 0.9 kg

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10. PRECAUTIONS FOR USE
11. SIMPLE CHECK AND HANDLING
1. No power : Check whether the adapter is good or not, whether the power plug or power
wire is good or not. If not,please change the power wire. Then check whether the indicator
of adapter is on or not, whether there is 24V DC power output, if no, please change a new
adapter.
2. No sound after connecting amplier with speaker : Check whether the speaker is overload
and simultaneously check whether the speak is short circuit. Check whether there is output
in amplier after the speaker is regular.
3. Too big noise : Check whether the connection of the devices is good, whether it is with
shield, whether it is overload or whether the audio signal is too big.
1. When amplier is working , volume control (controlled on mixer) is from small to big, until
moderate. When close it, volume control (controlled on mixer) is from big to small, then close
it.
2. During amplier working process, it cannot be changed the work pattern of ampliers or
the overload of speakers by random or else, it will damage the amplier easily. Usually, it
should conrm the work pattern.
3. During amplier working process, it cannot be changed the plugs of every audio devices
in acoustic amplication system by random, including the plug of mixer. Or else, it will easily
cause pulse signal, then from HPPMW by amplier, until lead to LNB of audio, make the
LNB burned and amplier overload then destroy the amplier.
4. Prohibit overload during amplier connection as per rated power.

Linear Technologie • 11 rue du Puits Rochefort • 42 100 Saint-Etienne
Tél: [phone] • Fax: [phone] • www.lineartech.fr