bel Digital Audio BCR A4-4 OB User manual

Bel BCR A4-4 OB
Audio confidence monitor
User’s Guide Version 1.2

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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BEL!(Digital!Audio)!Ltd.!has!made!every!effort!to!ensure!the!accuracy!of!information!contained!
within!this!document!which!is!nevertheless!supplied!for!information!purposes!only!and!does!not!
constitute!any!form!of!warranty!or!guarantee.!
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All!trademarks!acknowledged.!
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The!information!in!this!document!is!subject!to!change!without!notice.!
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Bel (Digital Audio) Ltd.
Unit 3
Horwood Court
Bletchley
Milton Keynes
Bucks
MK11RD
Tel: [phone]
Email: [e-mail]
Web: www.beldigital.com

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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Contents
CONTENTS...............................................................................................................................3
INTRODUCTION.......................................................................................................................4
Front panel controls.................................................................................................................................4
Balance/ Left level.................................................................................................................................4
Input selector..........................................................................................................................................4
Input level indicators .............................................................................................................................4
AES lock indicators ...............................................................................................................................4
Anti-phase indicator...............................................................................................................................4
Right level..............................................................................................................................................4
Headphone jack......................................................................................................................................4
Power on indicator.................................................................................................................................4
Rear panel.................................................................................................................................................5
Mains input ............................................................................................................................................5
Audio inputs...........................................................................................................................................5
Line outputs ...........................................................................................................................................5
FIG 1.1 BCR A4-4 OB FRONT PANEL ....................................................................................6
FIG 1.3 BCR A4-4 OB LINK SETTINGS .................................................................................. 7
Audio input pin connections ...................................................................................................................8
BCR A4-4 OB SPECIFICATION............................................................................................... 9
Audio Specification ...............................................................................................................................9
General...................................................................................................................................................9
EMC compliance....................................................................................................................................10

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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Introduction
The BCR A4-4 OB is a professional audio confidence monitor housed in a
reduced depth 1U rack. The unit features four amplifiers, four speakers and an
analogue line output. The BCR A4-4 OB will accept four pairs of analogue and four
pairs of AES3 audio inputs.
Front panel controls
Several controls and connectors are located on the front panel, Fig 1.1, from left to
right these are:
Balance/ Left level
In the stereo mode this control will adjust the balance between the left and right
speakers. In the two-channel mode this control will adjust the left speaker output level. The
mode can be selected by adjusting the links shown in Fig 1.3
Input selector
The audio input pair routed to the amplifiers and speakers can be selected using this
switch. The first four positions are analogue inputs and the last four AES inputs.
Input level indicators
Two LED bar graph PPI displays indicate the current input level.
AES lock indicators
Four LED indicators show the locked state of the four AES inputs.
Anti-phase indicator
A single LED will illuminate to indicate sustained anti-phase on the selected inputs.
Right level
This control adjusts the right speaker output level.
Headphone jack
A 6mm headphone jack is provided on the front panel. Inserting a jack plug will mute
the speakers.
Power on indicator

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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Rear panel
Several connectors are provided on the rear panel, from left to right these are:
Mains input
This is a combination IEC connector, fuse and off/on switch.
Audio inputs
Four BNC connectors are provided to receive the AES3 digital audio input pairs 1 to 4.
A 25 way D type connector is provided to receive the analogue audio input pairs 1 to 4. These
inputs are treated as stereo pairs or two independent channels as selected by the internal
links. Fig 1.3.
Line outputs
Two male XLR type connectors are provided that carry a line level analogue audio
output.

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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Fig 1.1 BCR A4-4 OB Front panel
Fig 1.2 BCR A4-4 OB Rear panel

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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Fig 1.3 BCR A4-4 OB link settings

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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Audio input pin connections
Analogue audio inputs
Pin
Function
1
2
Left 1 +
Left 1 –
3
Ground
4
5
Left 2 +
Left 2 –
6
Ground
7
8
Left 3 +
Left 3 –
9
Ground
10
11
Left 4 +
Left 4 –
12
13
14
Ground
Ground
Ground
15
16
Right 1 +
Right 1 –
17
Ground
18
19
Right 2 +
Right 2 –
20
Ground
21
22
Right 3 +
Right 3 –
23
Ground
24
25
Right 4 +
Right 4 –

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
9
BCR A4-4 OB Specification
Audio Specification
Analogue inputs 4 Pairs differential, 25kΩimpedance on
25 way female D type connector
Analogue outputs 50Ωimpedance differential on XLR connector
AES digital inputs 4 independent pairs of AES3 digital audio, 75Ωon
BNC connectors.
AES sample rate 32kHz to 96kHz
Hum & noise main output more than 80dB below full output.
Hum & noise line output 100dB below full output
Peak acoustic output 100dB SPL (@ 2ft)
Level meters 2x10 element LED PPI bar graphs
Speakers 2 mid/treble and 2 bass
General
Power requirements 90-260 VAC 40/60Hz
Power consumption 30W Max
Dimensions 483mm x 200mm x 44.3mm
Weight 4kg

BEL DIGITAL AUDIO BCR A4-4 OB
©2017 BEL Digital Audio Ltd.
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EMC compliance
The BEL BCR series was designed and tested to comply with the EMC
directive numbers EN55103, EN55022 and EN55082-1 when used as directed.
It is recommended that, where possible, all cables be good quality screened
twisted pairs with the screening braid connected to pin 1 on the XLR
connector. Optimum performance is obtained using double-screened cable
with separate ground returns.