The RCM-4 Room Combining Module provides
the means for simplified, central control of
zone-combining and source selection functions
in commercial sound systems.
Several kinds of control signals may be issued
by the RCM-4. Used with a compatible mixing
matrix system, such as the Oxmoor RMX-44, the
RCM-4 will generate the signals required to
cause multiple sound systems to be combined to
form a single system. In hotels or convention
centers, for example, systems in adjacent meeting rooms may be combined when moveable
partitions are open to form a single, large hall.
Through the RCM-4, a user may also select
which source, or combination of sources, is to
be used in the combined system. The operator
may simply push a button, for example, to dictate that a particular end of the room will be the
location of the head table or entertainment. By
not selecting the sources of any of the other
combined zones, the possibility that they might
contribute hum or other undesired noise is
eliminated.
The user may just as easily select multiple
sources, making it possible to plug microphones
or other audio sources into any desired inputs
within the combined zones.
The RCM-4 may be used to link remote volume
controls of multiple systems, using Oxmoor Corporation, LLC’s DCA-2 Digital Control Attenuator and RC-16 Remote Controls (Figure 3). This
may be accomplished with or without the room
combining function (Figure 5). Likewise, room
combining may be performed in systems with or
without remote volume controls.
In the example shown in Figure 4, no remote
volume controls are used. This leaves the Remote Control jacks available for other switching
purposes.
Page 1
(Callouts refer to Figures 1 and 2)
RCM-4 CALLOUTS
1. POWER LED - The front panel LED is illuminated
when the unit is on. The absence of an On/Off
switch is a performance safety feature, eliminating accidental shutdown during operation.
2. REMOTE CONTROLS - Female 6-pin modular
TELCO connectors. Channels are paralleled
when a combine command is given through the
CONTROLLER INPUT. While this may facilitate a variety of custom remote switching functions, it is primarily designed for linking
Oxmoor's RC-16 and RC-2 Remote Volume
Controls.
3. INTERNAL RELAY - Links the Remote Control
channels A, B, C, and D of the RCM-4 (i.e.: A to
B, B to C, C to D, D to A) when a combine command is given through the CONTROLLER INPUT.
4. MOMENTARY PULSE - When a zone combine
command is given through the CONTROLLER
INPUT, causing some remote controls to become linked, Pin 1 on the IN connector and Pin 6
on the OUT connector of each affected REMOTE
CONTROL line are momentarily shorted to
common. This is intended to be used with
Oxmoor's DCA-2 Digital Control Attenuator.
When the DCA-2 sees this momentary pulse it
will force all affected audio channels to a predetermined volume level.
5. CONTROLLER INPUT - Female, 15-pin, standard
D-sub connector. The CONTROLLER INPUT
provides access to RCM-4 control functions. Application of a latching type contact closure between the controller input pins and common
causes pre determined combinations of the
modular Telco connectors to be connected in
parallel. DC power of +5VDC @225mA is provided for powering LEDs, etc.
6. RMX CONTROL PORT- Female, 25-pin, standard
D-sub connector. This port provides control of
the Oxmoor RMX Mixing Matrix Products. Signals issued via the CONTROLLER INPUT
cause contact closures to occur between appropriate CONTROL PORT pins and common. The
RMX Mixing Matrix uses these signals to combine certain audio channels.
7. FUSE HOLDER - Replace only with approved
type of fuse in a rating appropriate to the mains
voltage, as indicated on back panel. (see SPECIFICATIONS).
8. POWER CONNECTOR - Standard IEC 3-pin connector for AC power cord. Use only with
grounded (3-wire) outlets. Cord sets are available for all world connection standards.
9. CHASSIS GROUND POST - Nuts on a threaded
stud conveniently enable the installer to secure
the chassis to the sound system ground.
1
RCM-4 ROOM COMBINING MODULE
POWER
RCM-4
CHANNEL D
IN
161
OUTIN
6161
REMOTE CONTROLS
CHANNEL C
OUT
2
6
CHANNEL B
IN
161
OUTIN
6
CHANNEL A
161
CONTROLLER
OUT
INPUT
6
RMX CONTROL PORT
5
Figure 1.0: Front and Rear Panel Views of RCM-4
Page 2
POWER
FUSE
6
7
CHASSIS
SERIAL NUMBER
8
9
CONTROLLER INPUT
5
RCM-4 BLOCK DIAGRAM
L
O
G
I
C
4
6
RMX CONTROL PORT
L
O
G
I
C
3
3
3
L
O
G
I
C
1
6
3
IN
4
A
5
2
5
2
3
OUT
4
A
1
6
1
6
3
IN
4
B
5
2
5
2
3
OUT
4
B
1
6
1
6
3
IN
4
C
5
2
5
2
3
OUT
4
C
1
6
1
6
3
IN
4
D
5
2
5
2
3
OUT
4
D
1
6
2
REMOTE CONTROLS
Figure 2: Block Diagram of RCM-4 Room Combining Module
Figure 3 shows the Oxmoor four-room combining system. At the heart of the system is the RCM-4 Room Combining Module. The drawing includes a Control Panel
which serves as the module's user interface. The RCM-4
delivers both zone-combining and source-selection signals to an RMX-44 Mixing Matrix.
When combining zones, the RMX-44 mixes the appropriate signal sources (mixer outputs) within the combined
zones. Also, all RC-16 Remote Controls within the combined zones will be linked together and forced to a common preset level. This allows all RC-16s in each combined
zones to serve as master level controls over all speakers in
the combined system.
The RCM-4 Room Combining Module may be user con-
REMOTE
CONTROLS
PORT
PORT
D
IN
C
IN
B
IN
A
IN
OUT
OUT
OUT
OUT
OUT
IN
D
C
B
A
RMX CONTROL
CONTROLLER
RCM-4
figured for two different modes of operation when zones
are combined. One mode of operation allows the RMX-44
to mix all sources within the combined zones. Because all
sources within the combined zones are active, microphones, etc., may be plugged in wherever desired within
the combined zones.
The second mode of operation mutes the sources of the
combined zones, allowing the user to select a source or a
combination of sources to be used within the combined
zones.
The user can select where the head table will be –where
the entertainment microphones will plug in – without any
chance of hum, buzz, or ambient noise from unused
sources.
For the application shown, we recommend the Oxmoor RCS Room Combining System. When purchased as a package, the Room Combining System
*
offers substantial savings over the cost of the individual pieces. The Control Panel shown is one of four optional control panels offered only for the
RCS System. Input Source Select buttons are options on each Control Panel.
Page 4
RCM-4 APPLICATIONS (CONTINUED)
Figure 4 illustrates a typical four-room
combining system in which Remote
Volume Controls are not used. A
control panel is shown connected to the
CONTROLLER INPUT. This panel
would require four latching, SPST
contact closures in order to combine
adjacent channels. If individual source
selection is desired, four additional
SPDT latching contact closures are
required. To enable this option, tie pin 3
(source select option) of the Controller
Input to common. When this option is
used the activation of any zone combine
button will cause the sources to be
muted for the selected combination. The
sources select buttons may then be used
to un-mute the source.
Figure 4.0: Room Combining Without Remote Volume Controls
RMX-44 Mixing Matrix
CHANNEL A
CHANNEL B
CHANNEL C
CHANNEL D
CHANNEL COMBINE BUTTONSSOURCE SELECE BUTTONS
A+B
B+C
D+A
C+D
MIXER
MIXER
MIXER
MIXER
A
B
AMPLIFIER
CHANNEL A
AMPLIFIER
CHANNEL B
AMPLIFIER
CHANNEL C
AMPLIFIER
CHANNEL D
OUT
A
OUT
NOT USED
D
C
OUT
OUT
B
C
D
IN
REMOTE
CONTROLS
RMX CONTROL
PORT
CONTROLLER
PORT
A
IN
B
IN
NOT USED
C
IN
D
IN
CHANNEL A
CHANNEL B
CHANNEL C
CHANNEL D
MIXER
MIXER
MIXER
MIXER
NOT USED
OUT
OUT
OUT
OUT
IN
DCA-2
Attenuator
IN
IN
DCA-2
Attenuator
IN
D
C
B
A
REMOTE
CONTROLS
RMX CONTROL
PORT
CONTROLLER
PORT
RCM-4
AMPLIFIER
CHANNEL A
TYPICAL CONTROL PANEL
Volume Control
The system in Figure 5 combines
Oxmoor RC-16 Remote Controls
without combining audio sources. This
AMPLIFIER
CHANNEL B
approach would also be used in a
system which employs some unrelated
scheme for combining audio, such as a
patch bay, router, etc. Four latching
AMPLIFIER
CHANNEL C
SPST contact closures, tied to the
appropriate CONTROLLER INPUT
pins, allow combinations of adjacent
Remote Controls to be combined.
AMPLIFIER
CHANNEL D
This allows a choice of independent
channel volume adjustment, or combined remote controls that track
D
IN
C
IN
B
IN
A
IN
together.
Figure 5.0: Combining Remote Volume Controls
IN
RCM-4
A+B
TYPICAL CONTROL PANEL
Page 5
B+C
COMBINE BUTTONS
C+D
D+A
ZONE 8
ZONE 7
ZONE 6
ZONE 5
ZONE 4
ZONE 3
ZONE 2
ZONE 1
TO CONTROL
SYSTEM CLOSURES
MIXER
MIXER
MIXER
MIXER
MIXER
MIXER
MIXER
MIXER
RCM-4 APPLICATIONS (CONTINUED)
Zone Volume Control
AMPLIFIER
8
AUDIO
MIXING
MATRIX
OUT
OUT
OUT
OUT
REMOTE
CONTROLS
CONTROLLER
PORT
RCM-4
IN
DCA-2
Attenuator
IN
7
IN
6
DCA-2
Attenuator
IN
5
IN
4
DCA-2
Attenuator
3
IN
2
IN
DCA-2
Attenuator
1
IN
1
OUT
IN
2
OUT
IN
3
OUT
IN
OUT
4
IN
REMOTE
CONTROLS
CONTROLLER
IN
3
IN
4
IN
5
IN
6
PORT
RCM-4
5
OUT
IN
6
OUT
IN
IN
7
OUT
IN
8
OUT
IN
REMOTE
CONTROLS
CONTROLLER
PORT
AMPLIFIER
AMPLIFIER
AMPLIFIER
AMPLIFIER
AMPLIFIER
AMPLIFIER
AMPLIFIER
IN
IN
ZONE 8
ZONE 7
ZONE 6
ZONE 5
ZONE 4
ZONE 3
ZONE 2
ZONE 1
1
2
3
4
TO CONTROL
SYSTEM CLOSURES
5
6
7
8
TO CONTROL
SYSTEM CLOSURES
ROOM LAYOUT
ZONE 1ZONE 2
ZONE 4
ZONE 5
ZONE 8
CONTROL
LINE # 1
CONTROL
LINE # 2
ZONE 3
ZONE 6
ZONE 7
RCM-4
TO CONTROL
SYSTEM CLOSURES
Figure 6.0: Eight-Zone Combining System
Page 6
CONTROL
LINE # 3
RCM-4 APPLICATIONS (CONTINUED)
Figure 6.0 illustrates the switching flexibility that
may be realized by using multiple RCM-4 Room
Combining Modules. In this example, up to eight
Oxmoor RC-16 Remote Controls can be combined.
Control line #1 provides linkage between two,
three or all four of the zones designated 1 through
4. Control line # 2 and its RCM-4, offers identical
room combination possibilities within zones 5-8.
Control line # 3 goes to a third RCM-4 which
allows the same kind of combining within zones 3-
6. This RCM-4 adds the significant advantage of
allowing zones 3 and 6 and zones 4 and 5 to be
linked. This makes it possible to combine any of the
first four zones with any of the last four.
Figures 6.1, 6.2 and 6.3 show the combinations
available from system closures connected by
BC D
2
1
1
3
4
3
6
7
4
5
5
6
7
8
8
2
3
6
7
Figure 6.1:
Room Combinations
Using Control Line # 1
A
4
5
8
control lines to each RCM-4. The linking function
allowed by Control Line 3 and its RCM-4 makes
still more combinations available.
Note that multiple combined zones may be
operated concurrently. For example, the systems
described by Figures 6.1-I, 6.2-A and 6.2-C may be
selected to function simultaneously as three
separate systems.
If it is desired that zones 1-6 be combined, then all
control lines used to achieve Figures 6.1-I and
Figure 6.3-G must be taken to common. Similarly,
if all zones (1-8) are to be combined, all the
switching used to achieve Figures 6.1-I, 6.2-I and
6.3-G must be employed (all control lines to
common).
E
FG
1
1
1
2
4
3
5
6
8
7
2
4
3
5
8
7
2
4
3
4
5
6
6
5
8
7
8
H
2
4
3
5
6
8
7
I
1
2
4
3
5
6
8
7
Combined rooms are
shown by shaded area.
2
3
6
7
Figure 6.2:
Room Combinations
Using Control Line # 2
Figure 6.3:
Room Combinations
Using Control Line # 3
NOTE: Additional combinations are possible using all three control lines together.
12
4
3
5
6
8
7
A
12
4
3
5
6
8
7
BC D
2
1
4
5
8
2
1
3
3
4
5
6
7
6
7
8
2
1
4
3
5
6
8
7
BC D
2
1
3
4
5
6
7
8
2
1
4
3
5
8
7
2
1
3
4
5
6
6
8
7
Page 7
E
1
4
5
8
1
4
5
8
FGAH
1
2
4
3
5
6
8
7
E
FG
2
1
3
4
6
5
7
8
1
2
3
4
6
5
7
8
2
3
6
7
1
2
4
3
5
6
8
7
1
2
4
3
6
8
7
I
1
2
7
2
4
3
6
3
5
6
8
7
RCM-4 CONNECTIONS
(Please refer to Figure 7.0)
CONTROLLER INPUT
Female, 15-pin, standard D-sub connector.
Pin # Pin Assignment
1 ....................... Common
2 ....................... Common
3 ....................... Source Select Option
4 ....................... A + B Combine
5 ....................... B + C Combine
6 ....................... C + D Combine
7 ....................... D + A Combine
8 ....................... + 5 VDC@ 225mA
(same as pin 15)
9 ....................... Common
10 ..................... Common
11 ..................... A Source Select
12 ..................... B Source Select
13 ..................... C Source Select
14 ..................... D Source Select
15 ..................... + 5 VDC @ 225mA
(same as pin 8)
REMOTE CONTROLS
Channels A through D, female 6-pin TELCO
connectors.
INOUT
Pin #Pin #
16
25
34
43
52
61
RMX CONTROL PORT
Female, 25-pin, standard D-sub connector.
Low-voltage DC: Pins 8 and 15 of the RMX
Controller Port are identical, paralleled DC
outputs providing +5 VDC at 225 mA
maximum. This supply may be utilized to
power LED indicators, etc.
CHANNEL D
IN
161
OUTIN
6161
REMOTE CONTROLS
CHANNEL C
OUT
6
CHANNEL B
IN
161
OUTIN
161
6
CHANNEL A
OUT
6
CONTROLLER
INPUT
RMX CONTROL PORT
FUSE
CONTROLLER INPUT RMX CONTROL PORT
(WITH SOURCE SELECT OPTION TIED TO COMMON)
Pin # Shunted to Common ActionPIN # Forced to Common
4 ................................. A + B Combine12, 7, 22, 17, 8, 11
5 ................................. B + C Combine12, 7, 22, 17, 6, 23
6 ................................. C + D Combine12, 7, 22, 17, 18, 21
7 ................................. D + A Combine12, 7, 22, 17, 9, 20
4 & 5 ........................... A + B + C Combine12, 7, 22, 17, 8, 11, 6, 23, 24, 10
5 & 6 ........................... B + C + D Combine12, 7, 22, 17, 6, 23,18, 21, 19, 5
6 & 7 ........................... C + D + A Combine12, 7, 22, 17, 18, 21, 9, 20, 24, 10
7 & 4 ........................... D + A + B Combine12, 7, 22, 17, 9, 20, 8, 11, 19, 5
* .................................. A + B + C + D Combine12, 7, 22, 17, 8, 11, 6, 23, 24, 10,
18, 21, 20, 9, 19, 5
*Any three of pins 4 through 7.
Figure 7.0: Example Of Interaction Between The RCM-4 Controller Input and RMX Control Port
Page 8
RCM-4 SPECIFICATIONS
REMOTE CONTROLS
IN – Channels A, B, C, and D loop through to their respective outputs using 6-pin RJ-11 modular phone jacks.
OUT – Channels A, B, C, and D loop through to their respective inputs using 6-pin RJ-11 modular phone jacks.
INTERNAL RELAY – Links Remote Control Channels A to B, B to C, C to D, and D to A when a combine command is
given through the CONTROLLER INPUT.
INTERNAL RELAY
Contacts ........................ 4PST, Normally Open
Voltage ......................... 50 V
Current ......................... 100 mA
Switching Time ........... 10 mS
Bounce .......................... 75 uS
MOMENTARY PULSE
When a combine command is given through the CONTROLLER INPUT, Pin 1 on the Remote Control IN connectors
and Pin 6 on the Remote Control OUT connectors are momentarily shorted to common. This only applies to the
channels that are to be combined.
Circuit Type ................. Open Collector to Common
Switching Time ........... 13 mS
Duration ....................... 76 mS
CONTROLLER INPUT
Provides access to RCM-4 control functions. The RCM-4 control lines require a maintained closure to common in order
to execute a function.
Logic Action ................ Active Low, Requires Maintained Closure to Common
Control Lines ............... Internally Pulled Up to +5VDC
Input Protection .......... 1/2 Max. Line Voltage, 12 kV Static
Connector ..................... Female 15–Pin Standard D-Sub
Cable Length ............... 300m (1000 ft.) Maximum, Using #22 AWG
Switching Time ........... 13 ms
Power Output .............. +5 VDC ±0.1 V, 225 mA Current Limited to 250 mA
RMX CONTROL PORT
This control port was designed to control Oxmoor's RMX-44 Mixing Matrix. The RCM-4 provides closures to common on
the RMX Control Port pins which causes an RMX-44 Mixing Matrix to combine the appropriate audio channels.
Circuit Type ................ Open Collector to Common
Connector .................... Female 25–Pin Standard D-Sub
Parallel Outputs ......... 64 Maximum
Sink Current ............... 100 mA Maximum (Each Output)
Voltage ........................ 50 V Maximum
Cable Length .............. 600m (2000 ft.) Maximum, Using #22 AWG
FUSE TYPE
125 mA (1/8 amp) SB @ 115 VAC
63 mA (1/16 amp) SB @ 230 VAC
POWER REQUIREMENTS
100 to 125 VAC or 200 to 230 VAC
50/60 Hz; 13 Watts Maximum
MECHANICAL
Dimensions ................. 44 H x 482 W x 183 D mm; (1.72H x 19 W x 7.18 D in)
Finish ........................... Textured Black Paint
Weight ......................... Shipping: 3.8 Kg (8.5 lb), Net: 3.1 Kg (6.9 lb)
Specifications subject to change without notice.
Page 9
OXMOOR FACTORY SERVICE
For service information contact:
Oxmoor Product Service Department
309 Cahaba Valley Parkway
Birmingham, Alabama 35124
E-mail: info@oxmoor.com
Additional Installation & Operation Manuals are available from Oxmoor. Contact the
Oxmoor Sales Department for pricing and other ordering information. Consult
warranty statement for cautions concerning unauthorized service.
Oxmoor warrants that each Oxmoor electronic product shall be free from defects in workmanship
and materials and will, at its option, repair or replace any part of the product without charge
provided the product is delivered to Oxmoor within two years of date of original purchase from
or delivery by an authorized Oxmoor dealer. Excluded from this warranty are finish and
appearance items and malfunction resulting from abuse, from use that is not in accordance with
instructions, or operation under other than specified conditions. Also excluded are incidental or
consequential damages except where precluded by applicable law. This warranty provides the
customer with specific legal rights; there may also be other rights which vary from state to state.
Repair by other than Oxmoor Factory Service Department or its authorized service agency,
unauthorized modification, or the removal or defacing of the serial number will void this
warranty.
Products returned for factory warranty service must be prepaid and packaged in such a way as to
insure safe transit and must be accompanied by a sales slip or other valid proof of purchase date.
PRIOR AUTHORIZATION FROM OXMOOR IS REQUIRED FOR RETURN. Contact Oxmoor for
a Return Authorization (R.A.) Number and shipping information before returning product for
service.
CONTACT
OXMOOR
Oxmoor Corporation, LLC, 309 Cahaba Valley Parkway, Birmingham, AL 35124 USA