APART lsc4s User manual

LSC4S
Instruction manual
LSC4S

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Instruction manual
LSC4S
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LSC4S

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Loudspeaker comparator
Safety first!
• Please check the carton box for any kind of damage on
reception of the goods. In case of a damaged carton, please
contact your dealer before opening the carton.
• !!!! Danger !!!! Exposure to high sound levels may cause a
permanent hearing loss. Individuals vary considerably to sound
pressure level induced hearing loss but nearly everyone will
lose some hearing if exposed to high sound pressure levels
for a sufficient amount of time. Therefore it is recommended
that all persons exposed to equipment capable of producing
high sound pressure levels, such as this device, be protected by
hearing protection while installing or operating this unit.
• Read all documentation before operating your equipment.
• Keep all documentation for future reference.
• Save the carton and packing material even if the equipment has
arrived in good condition.
• Should you ever need to ship the unit, use only the original
factory packing.
• Do not spill water or other liquids into or on the unit.
• Make sure power outlets are conform to the power
requirements listed on the back of the unit.
• Do not use the unit if the electrical power cord is frayed or
broken.
• Always operate the unit with the AC ground wire connected to
the electrical system ground.

Instruction manual
LSC4S
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• Do not connect the inputs / outputs of amplifiers or consoles
to any other voltage source, such as a battery, mains source, or
power supply, regardless of whether the amplifier or console is
turned on or off.
• Power down & disconnect units from mains voltage before
making connections.
• Do not use the unit near stoves, heat registers, radiators, or
other heat producing devices.
• Do not operate equipment on a surface or in an environment
which may distort the normal flow of air around the unit. If the
unit is used in an extremely dusty or smoky environment, the
unit should be periodically “blown free” of dust.
• Do not remove the cover. Removing the cover will expose you
to potentially dangerous voltages.
• Do not drive the inputs with a signal level higher than that
required to drive equipment to full output.
• Do not run the output of any amplifier back into another input.
• In case of mal-function this device should be serviced by
qualified service personnel only.
• The apparatus may not be exposed to dripping or splashing and
no objects filled with liquids may be placed on the apparatus.
• The appliance coupler has to be readily operable to disconnect
the device.

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Loudspeaker comparator
CAUTION: a clipped or distorted audio signal at the input (overload)
will come out as a clipped or distorted signal at the output,
regardless of the output level and DSP processing power applied
to the signal. Clipping occurs when the signal and/or the applied
gain is too high, due to incompatibility of the signal level, a faulty
source, an impedance mismatch or a human error. Therefore,
monitor incoming signals and do not overload the inputs. Adjust
the output level(s) and gain settings of your source(s) if necessary.
Due to the internal gain structure of the LCS4S, the output signals
may clip even when the input signals are relatively low. Do not over
amplify audio signals. Boosting certain frequency bands or over
compressing incoming audio signals may cause signal clipping,
distortion and excessive noise at the output. If you have to add lots
of gain, your incoming signal may be too weak.
CAUTION
TO REDUCE THE RISK OF ELECTRIC SHOCK
DO NOT REMOVE COVER OR BACK
NO USER-SERVICEABLE PARTS INSIDE
SERVICING ONLY FOR QUALIFIED PERSONNEL
Caution

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LSC4S
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This device is NOT designed to be used as a music system.
The LSC4S is a 4 channel stereo speaker comparator, used as a
sales tool to compare the quality of up to 4 different speaker pairs.
Speaker comparing is mostly done in demo situations or audio
shops, to allow end users to hear the quality difference between
multiple speaker (-pairs).
The LSC4S is equipped with 2 stereo line inputs for source
connection (preferably CD player with highest quality) and 4 stereo
class-D amplified outputs. The unit has a built-in webserver and
WiFi Access Point for TCP/IP connection for control through any
mobile device or computer that has a web browser installed.
General description
• Internal webserver GUI for control
• Internal WiFi access point 2.4 GHz 150 Mbit/s IEEE802.11b/g/n
pre-configured
• Stand alone operation
• 2 stereo unbalanced line inputs using RCA connectors
• 2 stereo unbalanced line outputs using RCA connectors
• 8 x 30 W class-D amplifier outputs (6-12 Ω)
• Universal integrated switching power supply: 85-264 VAC /
47-63 Hz
• Front LED indication for active output
• Removable 19” rack ears
Features

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Loudspeaker comparator
Connections
Front panel
1. Output status: These LEDs indicate the active output. Only one
output can be active at any time. Both LEDs (left and right) of
the active output will be lit. The LEDs also indicate the status of
the amplifiers, when an amplifier output is short circuited, the
output LED will start to blink.
2. Power LED: illuminated when mains power is present and the
unit has been switched on.
3. Removable rack ears.
1 2 33

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LSC4S
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Rear panel
1. Power inlet: Connect the power cord here.
2. Power switch: Power the unit on and off.
3. Ampifliers: There are 8 class-D amplifiers in the LSC4S. Speakers
are connected with the included female euroblocks. Each
output is protected against short circuit, thermal overload and
DC error.
4. Line outputs: These are line level signal outputs which are a
copy of the amplifier’s outputs 3A, 3B, 4A and 4B. They can
be used to feed a signal to a larger external amplifier so that
higher powered speakers can also be driven as part of the
demonstration system.
5. Line input 1 and 2: The LSC4S has 2 stereo line inputs.
Line input 3 and 4: These connectors are not in use.
6. FM Antenna: This connector is not in use.
1
2 3
4 5 6

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Loudspeaker comparator
Connecting speakers
With the LSC4S, you can compare up to 4 stereo or mono speaker
sets. To connect mono speakers, leave outputs B not connected and
only use a mono source, connected to input A.
The following speakers can be connected:
• Small - medium sized
• Impedance: 6 - 12 Ω
The following speakers CANNOT be connected:
• 70 V, 100 V speakers
• Active speakers
• Subwoofers
Make sure to connect the plus from the speaker to the plus from
the output and the min from the speaker to the min from the
output. Never connect speakers in parallel or in series.
To compare speakers in an objective way, make sure that:
• All speakers have the same impedance. If not, the volume will
be different and this will influence the perception of the quality.
• Place the speakers at ear height.
• Use cables from LSC4S to the speakers with sufficient diameter
(minimum 1.5 mm²) and keep all cables as short as possible and
at same length.
• Use a high quality source (CD player) with original CD
recording, no copies.
• Choose a dynamic track with good low – mid – and high
frequencies.

Instruction manual
LSC4S
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Connecting your control device
• Start-uptheLSC4Sandwaitforsomeseconds.
• MakesureyourpcortabletisinDHCPmode.
• ScanyourWiFiNetworkcard(fromPCortablet)for
the SSID “LSC4S”.
• Inserttherequestedpassword“Comparator”.
• OnceconnectedtotheLSC4Snetwork,openyourwebbrowser
and open the link “http://192.168.1.10”. This link will open the
GUI to control the comparator.
IMPORTANT NOTE: Never use two or more LSC4S devices in the
same area since the internal WiFi access point uses the same SSID.
This will cause network conflicts.
If you need to compare more than 4 speaker sets, you need to
reconnect the speakers and do the comparing in two series or you
can use the ME-LCSS 16-channel speaker comparator.
The control of the LSC4S can be done from a wireless device such
as a tablet, PC, laptop, …
Be sure not to connect two or more control devices simultaneously
to the LSC4S.

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Loudspeaker comparator
Comparing speakers
Opening the link “http://192.168.1.10“ via your web browser will
open the GUI to control the comparator.
There are four “Out” buttons to activate the connected speakers.
Pushing “Out 1” button will switch OFF all speakers except the
speakers connected to output 1A and 1B. Pushing “Out 2” button
will switch OFF all speakers except speakers connected to output
2A and 2B and so on.
In this way you can compare easily the quality of multiple speakers.
There is no possibility to play multiple outputs simultaneously.
Note that there is no Equalizing of the signal, all speakers use the
same source, the same pre-amplifier and identical power amplifiers.
The MUTE button will switch OFF all speakers. To continue the
comparison, just click one of the four Out buttons.
With the Source buttons, you can switch over from Line Input 1
to Line Input 2 or vice versa. This selection will switch all outputs
simultaneously.
The volume slider will increase or decrease the volume of all
outputs simultaneously. When the volume of channel 1 is increased
and then channel 2 is selected, the volume of channel 2 will be
increased as well. In this way, the speakers will be compared at
equal volume level.

Instruction manual
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Loudspeaker comparator
Specifications
Unbalanced stereo inputs
Input impedance 10 kΩ
Input sensitivity 940 mVrms
Maximum input voltage 3.5 Vrms
Amplifier Outputs 1- 8
Minimum load 6 Ω
Maximum output level +26 dBV
SNR 98 dB @ 1 % THD, 1 kHz
THD-N full power - 6 dB @ 1 kHz 0.061 %
Noise floor -74 dBV
Noise floor muted -119 d B V
Channel separation
Line input to amplifier
output ch1A – ch1B
84 dB @ 1 kHz, 65 dB @ 20 kHz
@ full power with 8 Ω load
Power supply
Power supply SMPS
Input voltage range 85 - 264 VAC
Maximum power 150 W
Dimensions and weight
W x D x H 484 x 316 x 44 mm
Net weight 4.1 kg
Amp topology
class-D

Instruction manual
LSC4S
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WiFi Access Point
2.4 GHz
IEEE802.11b/g/n compatible
150 Mbps maximum
WPA2-PSK
I P 19 2 .16 8 .1.1
255.255.255.0
DHCP range 19 2 .1 6 8 .1.15 0 - 19 9
SSID LSC4S
PSWD Comparator

Loudspeaker comparator
developed
by
Audioprof nv
Industriepark Brechtsebaan 8 bus 1
2900 Schoten - Belgium
Company names, product names and trademarks are property of their
respective owners.
Apart-Audio specifications are subject to change without notice.