LA Audio BCL20 User Manual

Dual/Stereo Broadcast Compressor/Limiter

Operation Manual

August 2004

CONTENTSCONTENTS

1.1. IntroductionIntroduction

2.2. InstallationInstallation

3.3. WarrantyWarranty

4.4. Description of controlsDescription of controls

5.5. ApplicationsApplications

6.6. SpecificationsSpecifications

7.7. Front panel blanksFront panel blanks

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1.0 INTRODUCTION1.0 INTRODUCTION

The BCL20 is a stereo compressor-limiter with a de-essing
capability which allows the end user to process two different
signals or one stereo program.

Applications include :Applications include :

mastering, SPL limiting in PA and discotheque applications,
tightening of drums and sustain control on guitars and bass.

Main parametersMain parameters

times and compression ratio are user controllable.
A unique feature of the BCL20 is the continuously variable
detection characteristics. A potentiometer allows mixing of RMS
and Peak detectors to tailor the timing parameters to the
program being processed. The BCL20 takes advantage of a
unique transformer distortion cancelling circuit reducing it an
order of magnitude compared to conventional designs.
2 bargraphs display the amount of compression and the
input/output level. The de-essing functions involves a slew-rate
sensitive network which, while keeping operation very simple,
allows frequency-conscious compression, in accordance with
FM transmission or disc mastering pre-emphasis.
A rear panel jack allows insertion of an external equaliser to
achieve more specific frequency-conscious processing.
RFI protection has been a main concern in the design of the
BCL20 allowing its use in broadcast installations.

FM transmitter protection, disc

, including threshold, gain, attack and release

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2.0 INSTALLATION2.0 INSTALLATION

IMPORTANT: PLEASE READ THIS SECTION BEFORE USING THE BCL20IMPORTANT: PLEASE READ THIS SECTION BEFORE USING THE BCL20

2.1 INSPECTION AND UNPACKING2.1 INSPECTION AND UNPACKING

The BCL20 has been carefully packed at our factory in a carton
designed to withstand handling in transit. Should the unit appear
to have been damaged in transit notify your dealer immediately
and do not discard any of the packing. The carton should
contain -

• The BCL20 unit

• Power cord

• Operator Manual (this book)

2.2 OPERATING ENVIRONMENT2.2 OPERATING ENVIRONMENT

The BCL20 is designed to operate between 0 and 50°C (32­122°F) with relative humidity no more than 80%. Should the unit
be installed in an equipment rack, ensure that the ambient
temperature conforms to these levels.

2.3 CE STANDARDS AND THE LOW VOLTAGE DIRECTIVE (LVD)2.3 CE STANDARDS AND THE LOW VOLTAGE DIRECTIVE (LVD)

The BCL20 has been designed to meet the latest
Electromagnetic Compatibility (EMC) regulations. However we
recommend you do not operate the unit close to strong emitters
of electromagnetic radiation such as power transformers,
motors, mobile telephones or radio transmitters.

The unit should only be connected to a power supply of the type
described in 2.4 POWER REQUIREMENTS or as marked on the
unit. The unit must be earthed for safe operation. Disconnect the
mains supply before removing the cover.

2.4 POWER REQUIREMENTS2.4 POWER REQUIREMENTS

There is a mains fuse located inside the unit which is accessed
by removing the cover. This fuse is for protection against unit

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faults and as such will not normally need replacing. If you think
you have a power related problem please refer to your dealer.

The voltage and fuse rating have been factory set for ­230V 100mAUK

220V 100mARepublic of Korea
115V 200mANorth America

•• The correct voltage and fuse rating is indicated on theThe correct voltage and fuse rating is indicated on the
rear panel.rear panel.

•• Please check that your Please check that your unit is correctly rated for theunit is correctly rated for the
voltage of the country of operation.voltage of the country of operation.

If the fuse requires changing at any time please ensure the
correct fuse is fitted. An incorrect fuse could cause damage to
the unit and may constitute a fire hazard.

If you carry your BCL20 from one country to another it is very
important to ensure the voltage is compatible.

For your information the unit can be internally rewired for use in
230V, or 110-125V countries - contact your dealer for
information. A special 100V version is available for Japan and a
220V, 60Hz version for Republic of Korea.

The mains lead connections to the appliance are coloured in
accordance with the following code:

Green-and-YellowGreen-and-Yellow EarthEarth
BlueBlue NeutralNeutral
BrownBrown LiveLive

WARNING:WARNING: THIS APPLIANCE MUST THIS APPLIANCE MUST BE EARTHEDBE EARTHED

•

2.5 EXTERNAL CONNECTIONS2.5 EXTERNAL CONNECTIONS

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