MUSTANG
COMMUNICATIONS
MACRO SYSTEM AMPLIFICATION
INSTALLATION, COMMISSIONING & MAINTENANCE
HANDBOOK
Issue No.6
SCOPE OF THIS ISSUE:
M/8M
M8/M
M1008
M2508
M100/S
M250/S
M1008/D
M2508/D
M100/SD
M250/SD
Input modules
Standard options
Mustang Communications Ltd
Eastfield Industrial Estate
Scarborough
England
YO11 3UT
Telephone U.K. 01723 582 555
Telephone International 44 1723 582 555
Fax U.K.
Fax international
01723 581 673
44 1723 581 673
Email
Web
MACRO range installation manual. Issue 6
Author: M. R. Tetley M. Inst. S. C. E.
________________________________________________________________________
INDEX
............................................................................................................................... page
Introduction ....................................................... ....................................................... 5
- The Company and its quality statement......................................... 5
- The MACRO system concept and applications ............................. 5
General specifications .............................................................................................. 6
Front panel controls and indicators ................................ .......................................... 6
Tone control & Master gain adjustment ............................. ..................................... 6
Input module system ............................................... ................................................ 7
- module installation .......................................................................... 7
- module range .................................................................................. 7
- features & general specifications ................................................... 8
- input connections ............................................................................ 9
- module adjustments........................................................................ 10
Priority input facilities .......................................... ..................................................... 10
- priority/passive setting of modules ................................................. 12
- priority memory ............................................................................... 12
Pre-announcement chimes ............................................ .......................................... 12
Mixer facility connections - 0dB signal access point .............. ................................. 12
- 0dB signal in/out access for mixers & mixer amplifiers ................. 12
- input connections for slave amplifiers ............................................ 12
- tape recording ................................................................................. 13
- tape playback .................................................................................. 13
- interconnection of several amplifiers ............................................. 13
Power amplifier module ............................................ ............................................... 14
Loudspeaker output ................................................. ................................................ 14
- typical loudspeaker load arrangements ......................................... 15
Auxiliary output connections ...................................... ............................................. 16
- Priority controlled DC current sinks ................................................ 16
- Chime duration monitor sinks (CDM) ............................................. 16
- 100V line output .............................................................................. 16
- 24V DC supply ................................................................................ 16
Combining the loudspeaker outputs of two or more amplifiers .................................. 17
Power supply ........................................................................................................... 17
- AC mains power input ..................................................................... 17
- DC power input................................................................................ 17
- Systems powered by both AC and DC supplies ............................ 17
- Main ON-OFF front panel switch .................................................... 17
- Error status indicator LED .............................................................. 19
- Power status indicator LED ............................................................ 19
- Power supply failure monitoring ..................................................... 19
- Power supply change-over ............................................................. 20
- Battery charger circuit ..................................................................... 20
Earthing & hum loops .............................................. ................................................ 20
Factory fitted options ............................................ ................................................... 20
- Free-standing case ......................................................................... 20
- Automatic level control ................................................................... 21
- Balanced line input for M/100 and M/250 slave amplifiers............ 21
- Line surveillance ............................................................................. 22
Installation ...................................................... ......................................................... 22
- selection of signal input cables ...................................................... 22
- selection of loudspeaker cable ....................................................... 22
- fitting Locking DIN connectors ....................................................... 22
- siting ................................................................................................ 23
- ventilation ........................................................................................ 23
- interference ..................................................................................... 23
- removal of control knobs ................................................................ 23
- checklist .......................................................................................... 23
Fuses .......................................................... ............................................................ 24
Faults - symptoms and check-list ................................. .......................................... 24
Repairs and maintenance ........................................... ............................................ 24
- free-standing case removal ............................................................ 24
- removal of main pre-amplifier circuit board ................................... 24
Warranty .......................................................... ....................................................... 24
Electromagnetic compatibility (EMC) directive 89/336/EEC and amendment directive 92/31/EEC
This equipment has been designed and manufactured to the highest standards. If connected and operated as set out in this manual, there should be no
Electromagnetic Compatibility problems. If any aspect of operation gives rise to concern, then please contact the manufacturer for advice.
Page 3
PAGE
Table 1
Table 2
The current range of input modules
Module adjustments and settings
8
11
Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Location of Treble, Bass, and Master gain controls
Input connector pin identification
Location of priority sequence setting switches
Mixer facility connections for standard locking DIN connector
Mixer facility connector pin identification
Tape record and playback connections
7
10
11
12
12
13
14
15
18
19
21
Interconnection of several amplifiers
Power amplifier module fixings and adjustments
Priority connections for multiple amplifier systems
AC & DC supply connections and monitoring
Balanced line input connections
Block schematic diagram
Typical priority control and auxiliary arrangements
Typical loudspeaker circuits
Chassis layout & main component identification
Locations of module adjustments and fuses
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
Page 4
MACRO range installation manual. Issue 6
INTRODUCTION
Thank you for purchasing this unit. We are confident that you have made a wise decision, and that you will have many years of
trouble-free operation. Considerable care has been taken during the design and manufacturing processes to ensure your entire
satisfaction and naturally, we would hope that the unit will perform to our design expectations, though this will be possible only if
the installation is in line with professionally accepted standards and techniques.
This manual is intended, therefore, to ensure that both the installer and operator have all the necessary information to enable them
to install, commission, and operate the unit in the most effective manner. We hope you will find the manual helpful, and easy to
read.
The Company and its quality statement
Mustang Communications, is the manufacturing mark of equipment manufactured by Mustang Communications Limited, of
Scarborough, England. The company is independent, wholly British, and dedicated to the manufacture and distribution of high-
reliability, high performance public address and associated control equipment. Mustang Communications was first registered in
1966, in England.
The Company undertakes to manufacture equipment to the highest standards of workmanship and performance. Our Quality
Assurance scheme operates to, or exceeds, the standards set out in British Standard BS.5750, Part 2. 1987 or European
standard ISO.9002. If you have cause to doubt at any time that the manufacture, or distribution does not comply, then you are
invited to write to us with your comments, which will be most welcome.
Please address your correspondence to The Engineering Director.
The MACRO system concept and applications
MACRO System is a comprehensive range of AC mains and AC mains/24V DC amplification, controls and surveillance units and
associated peripherals, designed for use by emergency services and high integrity communication and alarm systems, manufactured
to the highest standards of electronic and mechanical performance and with Quality Assurance to British Standard BS.5750 AC/
DC equipment is designed to operate normally from 220/240V AC mains, with the capability to operate indefinitely, and without
loss of any facilities, from a standby DC power source (battery system) in the event of mains failure.
Full compatibility within the MACRO range is assured, thus easing system design and enabling fully integrated systems to be
specified using standard MACRO components and options.
The current manufacturing programme features a variety of 8 input mixers, 100 Watt and 250 Watt 8 input mixer amplifiers and
corresponding slave amplifiers, all offered in AC mains only or AC/DC format. AC/DC units provide full AC and DC power integrity
monitoring and indication, and all except mixers feature a trickle-charge circuit as standard. Mixer input versions accommodate
up to 8 modules, selected from the comprehensive range of microphone, line input and alarm tone generator modules. These are
plugged into an internal mother board system which generates 8 levels of ladder priority, equal access priority or any combination
of both. Priorities may be set up easily at system commissioning stage. The module circuits feature various aspects of memory
trigger, priority sinking for use with MACRO zone controllers, remote relays, system busy indicators etc., and such functions are
taken to a rear “D” connector. Each module is associated with a front panel gain control whose knob and spindle may be removed
at commissioning stage and replaced by a discreet blanking plug to discourage unauthorised tampering. Line driver and stabilised
low voltage PSU facilities are also on plug in modules. Treble and bass tone, and master gain adjustments are internal and pre-
settable.
The amplifier power output stage is in the form of a self contained bolt-on pluggable module for ease of maintenance, and pre-set
adjustment for sensitivity, overload threshold, and bias are featured. Output devices are very robust bipolars and errors on the
module are notified by a front panel LED. Other front indicators are a segmented bargraph output VU, AC (and DC where
appropriate) supply input monitoring, and an illuminated power switch. A soft-start DC switch on circuit is employed. The transformers
employed in MACRO amplifiers are in-house designed and manufactured to the highest standards of tolerance and quality to
maximise the efficiency of the electronics.
Mechanically, MACRO amplifiers utilise a 3U 19" rack mount format with plated steel chassis, contoured aluminium alloy anodised
front/rear panels, chromed handles, nut and bolt fastenings, and connectors are tough locking DIN as standard for signals, “D”
connector for auxiliary control functions, IEC mains, and military specification 97 series DC input.
By appropriate choice of input modules, the MACRO range of equipment will perform with outstanding results in a multitude of
applications, and a few only are listed under:-
Factory paging, time signals and alarm amplification
Retail stores paging and background music
Theatre show relay and prompt calls etc.
Multi-zone exclusive paging using one amplifier
Shopping centre automatic “spot announcements” and
security paging etc.
Zoned fire alarm systems
In use the amplifiers will give trouble free and accurate performance, and failure or partial failure is likely to be a result of external
problems with loudspeaker or input cabling etc. The following pages will provide a guide to setting up, operation and maintenance
of the amplifier, but in case of difficulty it would be advisable to consult a qualified dealer or the manufacturer.
Page 5
MACRO range installation manual. Issue 6
GENERAL SPECIFICATIONS
MIXER AMPLIFIERS
M1008
M1008/D
M2508
M2508/D
Input channels
8
8
Input channel level & response
Treble & Bass adjustment
Power output (Watts RMS contin.)
Current sinks
Auxiliary DC output
Mixer facility level
dependent upon input modules fitted
± 12dB @ 100Hz & 10kHz ref.1kHz
100
250
250mA maximum, each channel module
nominally +24V. 1A fused.
775mV nominal. 0dBV
Power amplifier input
Power amplifier power freq. resp.
775mV , 0dBV @ 10k ohms
-3dB @ 20Hz & 20kHz ref. 1kHz, low imp
-3dB @ 20Hz & 15kHz ref. 1kHz, 100V
100V/50V line balanced
240V 50-60Hz +5% -15%
6 Amp
350mA
Loudspeaker matching
AC mains supply input
24V DC supply input (22-28V)
DC quiescent consumption (approx)
18 Amp
350mA
SLAVE AMPLIFIERS
M100
M100/D
M250
M250/D
Power output (Watts RMS contin.)
Audio input level
Power amplifier power freq. resp.
100
775mV, 0dBV @ 10k ohms
-3dB @ 20Hz & 20kHz ref. 1kHz, low imp
-3dB @ 20Hz & 15kHz ref. 1kHz, 100V
100V/50V line balanced
240V 50-60Hz +5% -15%
6 Amp
250mA
250
Loudspeaker matching
AC mains supply input
24V DC supply input (22-28V)
DC Quiescent consumption (approx)
18 Amp
250mA
MIXERS
M8M
M8M/D
Input channels
8
8
Input level & response
Treble & Bass adjustment
Current sinks
Auxiliary DC output
Audio output level
AC mains input
24V DC supply input (22-28V)
DC quiescent consumption (approx)
dependent upon input modules fitted
± 12dB @ 100Hz & 10kHz ref.1kHz
250mA maximum, each channel module
nominally +24V , fused 1A
775mV nominal. 0dBV
240V 50-60Hz +5% -15%
—
—
250mA (module dependent)
150mA
FRONT PANEL CONTROLS & INDICATORS
By design, user accessible controls are kept to a minimum to avoid inadvertent maladjustment which could render the system
ineffective.
Each input channel of a MACRO mixer or mixer-amplifier may be adjusted for gain by using the front panel controls. Should the
commissioning engineer deem it prudent, he may remove any of the complete control knob/spindle assemblies, after adjustment
is complete, simply by pulling the knob. The resulting holes may then be blanked off using the blanking plugs supplied. The
controls may be refitted at any time subsequently. Slave amplifiers to standard specification are not fitted with a front gain control.
An illuminated power switch controls AC power input (and if applicable, DC power input simultaneously).
A series of LED indicators provides a simple means of assuring the user of correct amplifier operation. A 10 segment ladder gives
an indication of output level expressed in decibels - i.e. dB relative to maximum output amplitude. Under normal programme
conditions this will fluctuate between the extreme left and extreme right segments in accordance with the amplitude of the programme
at any particular instant. No segment is illuminated when the amplifier output is zero. If the illuminated segment is predominantly
to the extreme right (maximum) then it is likely that the amplifier is being over-driven and that the resulting sound will be distorted
on peaks. Reduce the corresponding front input gain control accordingly.
A fast attack/slow decay circuit is used to drive the display so that amplitude peaks are recognised.
Two further LEDs indicate the status of the power supply in use, and of the power amplifier module where appropriate. For further
details see page 19.
TONE CONTROL & MASTER GAIN ADJUSTMENT
Tone control facilities are provided on the line driver module, type TB.6 which is located at second right, on a mixer or mixer
amplifier when viewed from the front. Two trimmer potentiometers are located at the bottom of the module, just above the edge
connection tabs. Viewed from the front, the nearest is the bass adjustment and the furthest is the treble. Each controls a cut & lift
correction circuit with the central position of the rotator giving nominally flat response. At the extremities of rotation, the corrections
are ± 12dB at 100Hz and 10kHz respectively. Rotate controls clockwise to increase the gain at bass or treble frequencies. On
Page 6
MACRO range installation manual. Issue 6
Fig. 1 Location of Treble, Bass, and Master gain controls
leaving the factory, the controls will be set for level response. See Fig. 1
A conventional master level control is featured on the mother PCB between the line driver module (TB.6 etc) and the pre-amplifier
stabiliser module (PS.9 etc.) next to it. This control is set to maximum (fully clockwise) on leaving the factory. See Fig. 1
INPUT MODULE SYSTEM
The general accent of MACRO system amplification is towards flexibility of system design. Each MACRO mixer or mixer amplifier
will accommodate up to 8 purpose designed input modules selected from over 30 variations of pre-amplifiers, tone signal and
alarm generators. Any of the modules from the published list may be used in any of the 8 input channels of the amplifiers.
Modules are available to accept audio input signals for low-level processing from all known audio sources. Depending on type,
each module may be given a priority within the amplifier as described below. The chosen group of modules is set up within the
amplifier by the commissioning engineer to exhibit the required sequence of priorities for the specific sound system, and further
individually adjusted on the module for sensitivity, tone frequency, etc. These system adjustments are not directly accessible to
the user, who is confined to the front panel controls. Modules may be changed, removed, or adjusted at any time without
disturbance to the general operation of the system. Where priority sinking is featured, two alternative sinks are offered simultaneously
- “Any” priority, and “Individual input” priority. Therefore, external circuits such as relays, lamps, MACRO zone control systems
etc., may be triggered by any input channel or a specific input channel (or channels) by appropriate auxiliary connections. A
“Chime Duration Monitor” circuit, where fitted, gives “clearance-to-speak” information for paging systems via the “CDM” current
sink connection of the auxiliary output. Priority sinks and “CDM” current sinks operate independently of each other. The general
concepts are illustrated in APPENDIX B
Module installation
MACRO range amplification is intended for permanent installation, and consequently the plug-in concept of the modules does not
anticipate continuous or regular changing of modules. Whilst this is possible, the edge connector contacts may wear prematurely
and become intermittent and unreliable. Modules are located between vertical supports immediately behind the respective front
panel volume control, and only moderate force will be required when fitting or removing. DO NOT put pressure on the components
during this operation.
Module range
The range of input modules extends to cover all common functions though others may be added to suit demand. The current
range is shown below.
Page 7
MACRO range installation manual. Issue 6
MICROPHONE & LINE INPUT MODULES
M24
M26
M28
M30
L24
L25
L26
L27
L28
L29
L30
L31
L32
L33
L34
Universal low impedance transformer balanced, priority/passive
Low imp. transformer balanced, with priority, chimes and CDM
Low impedance transformer balanced, audio operated priority
Low impedance transformer balanced, priority/passive, phantom DC
600 ohm transformer balanced priority/passive, 50mV - .775V
10k ohm transformer balanced priority/passive, 50mV - .775V
47k ohm transformer balanced priority/passive, 50mV - 80V
600 ohm transformer balanced, priority, chime, CDM. 50mV - .775V
10k ohm transformer balanced, priority, chime, CDM. 50mV - .775V
47k ohm transformer balanced, priority, chime, CDM 50mV - 80V
600 ohm transformer bal., audio activated priority, 50mV - .775V
10k ohm transformer bal., audio activated priority, 50mV - .775V
47k ohm transformer bal., audio activated priority, 50mV - 80V
Aux unbalanced line, 50mV & .775V, priority/passive
Aux unbalanced line, 50mV & .775V, priority, chimes (no CDM)
NON-PRIORITY MODULES
E26
RIAA equalised 5mV @ 50K for magnetic phono cartridge
Flat response, 80mV to 1V for ceramic phone cartridge
TONE GENERATOR MODULES
T24
T25
T26
T27
T28
T30
T32
T34
1kHz sine wave generator, momentary triggering
Time pips, with timer, priority hold & memory
Repeating gongs with timer, priority hold & memory
Alternating dee-dah alarm with timer, priority hold & memory
Warble alarm with timer, priority hold & memory
Trimphone telephone simulator, momentary triggering
Triple chimes with timer, priority hold, & memory
Slow whoop with timer & priority hold
Table 1 The current range of input modules
Module features & general specifications
MICROPHONE INPUT MODULES
M24 M26 M28 M30
Transformer or Electronic balanced
Priority only or priority/passive option
Priority controlled current sink
Chimes & Chime Duration Monitor sink
Phantom DC supply
T
T
T
T
PP PO PO PP
4
4
4
4
4
4
4
Audio activated priority (VOX)
Bass cut facility
4
4
4
4
GENERAL SPECIFICATIONS - MICROPHONE INPUT MODULES
Sensitivity range
100uV to 2mV
Input impedance
Suitable for 200 ohm microphones
20Hz - 20kHz
Frequency response -3dB points
Bass cut response
-3dB @ 200Hz -6dB @ 100Hz
58dB minimum
Signal to noise ratio
Input overload capability
Sink capability (mA max. continuous)
Phantom supply
50dB
250mA
+15V via 1k0
VOX delay
3 seconds maximum
Page 8
MACRO range installation manual. Issue 6
LINE INPUT MODULES
L24 L25 L26 L27 L28 L29 L30 L31 L32 L33 L34
Transformer input or unbalanced
Priority operation only
Priority/passive switchable
Sensitivity 50mV - .775V
Sensitivity 50mV - 80V
Input impedance (ohms)
Priority controlled sink
Chimes
T
T
T
T
T
T
T
T
T
U
U
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
600 10k 47k 600 10k 47k 600 10k 47k 4k7 4k7
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
Chime Duration Sink
Audio activated priority (VOX)
4
4
4
GENERAL SPECIFICATIONS - LINE INPUT MODULES
Sensitivity range and impedance
Frequency response -3dB points
Signal to noise ratio
See above
20Hz - 18kHz
58dB minimum
50dB
Input overload capability
Sink capability (mA max. continuous)
VOX delay
250mA
3 seconds maximum
TONE GENERATORS
T24 T25 T26 T27 T28 T30 T31 T32 T34
Momentary or timed triggering
Adjustable tone frequency
Priority hold for tone sequence
Priority memory
M
T
T
T
T
M
T
T
T
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
Adjustable duration timer
4
GENERAL SPECIFICATIONS - TONE GENERATOR MODULES
Trigger switch requirements
Duration timer
1.5mA maximum @ +15V DC
2 - 30 seconds approx
Indefinite
Trigger memory capacity
Sink capability (mA max. continuous)
250mA
MISCELLANEOUS MODULES
Function
E26
Magnetic phono pre-amp
5mV@50k
Ceramic phono pre-amp
80mV-1V @ 1M
Flat
Sensitivity
Equalisation
RIAA
Input connections
Standard amplifiers are fitted with Locking 5 pin DIN input connectors on a 180 degree spacing pattern. See Fig. 2 below to
identify the pin numbers. The input connections will vary depending upon which module is being used in the corresponding
module position, as follows:
Balanced microphone & line input modules i.e. M24 to M30 and L24 to L32 inc.
Standard Locking 5 pin DIN -
Pin 1
Balanced input
Pin 3
Pin 2
Pin 4
Pin 5
Signal earth (cable audio shield)
Priority control (except audio activated modules)
Page 9
MACRO range installation manual. Issue 6
Auxiliary inputs and music modules i.e. L33, L34, E24, E25,
Standard Locking 5 pin DIN -
5 PIN DIN
STANDARD
CONNECTOR
Pin 1
Pin 2
Pin 3
Pin 4
Signal input
Signal earth (cable audio shield)
Signal input
Priority control (except E24, E25, T35)
Pin 5
Tone generator modules i.e. T24 to T34 inclusive
Standard Locking 5 pin DIN -
SOLDER CUPS
VIEWED FROM
INSIDE THE PLUG
BODY
Pin 1
Pin 2
Pin 3
Pin 4
No connection
No connection
No connection
Priority control & tone trigger
Pin 5
Fig. 2
Input connector pin identification
Locking 5 pin DIN connector plugs are not furnished automatically with the unit, and must be ordered as a separate item.
Module adjustments
Various adjustments are available on each module, dependent on type and function, etc and are shown in table 2. The general
locations are shown in APPENDIX E.
PRIORITY INPUT FACILITIES
Each MACRO amplifier (with input module facilities) can be programmed to provide up to 8 levels of signal priority which may be
arranged in a descending order access (sometimes referred to as ‘ladder priority’), or an equal access first-come-first-served
priority, or any combination of both. The modules available may be categorised into ‘priority’ and ‘passive’ modules, and it is the
‘priority’ modules which generate the ladder sequence. Thus if a MACRO amplifier were fitted with say five priority modules, then
obviously only a maximum of five levels of priority could be available. However, the amplifier containing the five modules may be
set up to exhibit ladder priority, for example, on inputs 1 and 2 whilst inputs 3-4-5 may be given equal access. This set-up could
now be referred to as exhibiting just 3 levels of priority.
Equal access is a form of priority whereby the first to access the priority chain locks out one (or more) other inputs for the duration.
As supplied from the factory, the amplifier will exhibit a ladder sequence downwards from input No.1 as first priority. Equal access
between any modules must be between physically adjacent modules, and is instigated by depressing the small blue PCB switch
button which is located between the module input sockets on the main mother PCB. See Fig. 3. Later units utilise a DIL or Molex
type switch, which should be set to ‘ON’. There are 7 such switches, and any number may be depressed at any time to give the
required priority arrangement.
MACRO systems may be designed to include music or other non-priority facilities, and the appropriate modules will have been
specified. All such modules are ‘passive’ modules and as such should occupy module sockets at the lowest end of the priority
chain. i.e. towards input No.8. Passive modules will be overridden by any priority modules in the chain, but have no facilities to
instigate any priority functions (such as current sinking) of their own.
In all cases, the priority functions of priority modules are triggered by bridging pins 4 and 5 of the DIN channel input socket. The
switching current is in the order of 2mA @ 15V. On successful access to the signal priority chain, the module circuitry will perform
certain functions:
a)
b)
c)
d)
e)
f)
Modules of equal or lower priority will be inhibited, whether of priority or passive format.
The audio signal path of the accessed module will be enabled
The channel current sink (250mA max) will be enabled
The ‘any channel’ current sink will be enabled (250mA max)
The modules in immediately higher priority will be inhibited if the equal access PCB switches have been set
The tone sequence of a tone generator module will be started either via the module timer circuit, or
momentarily for the duration of the trigger
g)
The chime sequence of a chime-microphone module will be triggered and consequently enable a CDM (chime
duration monitor) current sink to be energised (250mA max).
Should a module which is currently in an accessed mode be inhibited by the triggering of a higher priority module, all the above
functions (a) to g) where appropriate) will be lost immediately, for the duration. However the timer function will still be operative
and may re-enable the original module, if timing permits, when the higher priority is released.
Voice operated modules attempt to gain access by triggering on amplitude peaks and the resulting functions are consistent with
a) to e) above.
The audio paths of lower priority passive modules will be inhibited for the duration.
Page 10
MACRO range installation manual. Issue 6
FACILITY
USAGE or FUNCTION
Audio gain
Sets the level of amplification of incoming signal. Influenced by no other adjustment
Determines the level of chime tone to be injected. Influenced by no other adjustment
Sets level of audio input at which the VOX circuit is triggered. Influenced by ‘Audio gain’.
Temporarily set sensitivity to maximum, and set Vox delay to maximum to enable ‘Audio level’ to
be set using typical input signal, then reset ‘VOX sensitivity’ and then ‘VOX delay’.
Determines the time delay between cessation of audio input signal and release of priority and/or
muting of channel. Influenced by Audio gain and VOX sensitivity. Adjust those first.
Sets collective pitch of chime sequence. Tones may not be adjusted individually. Influenced by
no other adjustments.
Chime level
VOX sensitivity
VOX delay
Chime frequency
Bass cut link
Sensitivity link
Cut this link to introduce a sensitivity roll-off at bass frequencies. Particularlyeffective for paging
applications.
Cut link to change the scope of Audio gain adjustment to 50mV-2V, from 2V-80V RMS.
Priority/passive jumpers See relevant information on page 12
Timer duration
Sets period of on-board timer within the range 2-30 seconds, after which the priority is released
and tone ceases. Influenced by no other adjustments.
Output level
Sets level of audio tone output from module. Influenced by no other adjustment.
Tone generator frequency Sets audio pitch of tone generation sequence. Influenced by no other adjustments.
ALC threshold level
See Factory Fitted Options - Automatic level control, on page 21. Influenced by no other
adjustmen on this module.
ALC sensitivity
See Factory Fitted Options - Automatic level control, on page 21. Influenced by no other
adjustment on this module.
Surveillance tone level
See Factory Fitted Options - Line surveillance on page 22. Influenced by no other adjustment on
this module.s
Table 2 Module adjustments and settings
Fig. 3 Location of priority sequence setting switches
Page 11
MACRO range installation manual. Issue 6
Priority/passive setting of modules
Certain modules contain features enabling the commissioning engineer to set them to operate as normal priority modules, or as
passive modules. Referring to APPENDIX E, this is accomplished on the M24 microphone input module for example by transposing
the position of a jumper link on the module, from lower middle (position B) to lower left (position A) for the change to passive (non-
priority) mode. In this mode, the module audio signal path is permanently enabled, though it will be inhibited by access of any
higher priority module and is itself rendered unable to inhibit any other module. The jumper link may be changed at any time, and
is a simple push fit.
Priority memory
If, whilst a priority module is being accessed, an attempt is made to trigger a tone generator module which is installed in a lower
priority level, and which features a priority memory, then no apparent action will result until the higher priority is released, at which
time the memory circuit will automatically and immediately trigger the timer circuit of the module, causing it to operate in the
normal manner for its pre-set duration.
PRE-ANNOUNCEMENT CHIMES - all units except slave amplifiers
The customary ding-dong chime signals which can often be heard to precede announcements in public buildings, are generated
in MACRO range equipment by certain standard microphone or line input, and tone generator modules. It is possible therefore to
install two or more such modules, and adjust them so as to be readily distinguishable. The chime is triggered only on successful
access to the priority chain. See APPENDIX E for location of adjustments.
MIXER FACILITY CONNECTIONS - 0dB SIGNAL ACCESS POINT
This connection may be used to gain access to the output of the pre-amplifier section, or the input of the power amplifier section,
at 0dBV level. Standard connection is by Locking 5 pin DIN panel socket with 180 degree pin spacing pattern. Connections are as
follows:
Fig. 4 Mixer facility connections for standard locking DIN connector
0dB signal in/out access for mixers & mixer amplifiers -
The standard Locking DIN pin connections are as follows:-
5 PIN DIN STANDARD
CONNECTOR
Pin 1
Pin 2
Pin 3
Pre master gain control direct from TB.6 module
Signal earth (cable audio shield)
Post master gain control (via 10k source)
With the master control at position “0” the loading effect exhibited by pin 3 is
approximately 6k8 ohms. For further clarification of this arrangement see the
block schematic diagram - APPENDIX A
Input connections for slave amplifier
SOLDER CUPS VIEWED
FROM INSIDE THE PLUG
BODY
The standard input circuit is suitable for unbalanced line operation, and the locking
DIN signal input connections are:-
Pin 1
Pin 2
Pin 3
No connection
signal earth (cable braiding)
.775v @ 10k ohms power amplifier input
Fig. 5 Mixer facility connector pin
identification
Page 12
MACRO range installation manual. Issue 6
Signal arrangements and DIN cable connections are shown in Fig. 4
As a factory fitted option, a line input transformer may be fitted.
See page 21 for further details.
Slave amplifiers have a fixed sensitivity and no input control is provided on standard models. The input impedance is approximately
10k ohms. Immediate technical advice for specific problems is available from the Technical Services Department, Mustang
Communications Ltd. Please also see the section of this manual which covers earthing and earth/hum loops, on page 20.
Tape recording
The mixer facility socket of mixers and mixer amplifier units will provide suitable signals for tape recording, though it will normally
be necessary to make up a suitable recording and/or playback lead.
This socket is associated with the master gain control, so either pin 1 or pin 3 of the standard Locking DIN connector may be taken
as the signal connection dependent on whether the recorded signal is to be influenced by it:-
Pin 1
Pin 2
Pin3
signal non-dependent on master gain control
signal earth (cable braiding)
signal via master control
For recording on a stereo recorder connect both left and right channel signal input connections together to pins 1 or 3 as required.
The manufacturer’s handbook should be consulted to ensure that the recorder will accept signal levels of approximately 0.75V
without distortion and that the recorder does not short out the signal recording connections when in the playback mode. In either
case, insert a resistor of suitably high value in series with the recording lead. An experimental starting value would be 22k ohms.
See Fig. 6
Certain tape decks send a signal from the tape playback output during a recording session. If, in this case, the recording and
playback leads are connected simultaneously to an input channel of the amplifier, a closed-loop feedback path to the amplifier will
result and cause problems unless the loop is broken. This in its simplest form would necessitate disconnecting the tape playback
lead whilst recording, or alternatively, reducing to zero the amplifier input gain control associated with playback.
Tape playback
A playback signal would preferably be routed through a standard line input module (L25, L33, L34 etc) which accommodate a wide
variety of signal levels. The module may be located in any module position. The L25 for example has a floating input circuit, and
Fig. 6 Tape record and playback connections
would be most useful where hum loops are likely to be a problem - such as in complex sound installations. See the module details
for connection data. The module will need to be set to the “passive” mode of operation - see page 12.
Interconnection of several amplifiers
Larger scale amplification systems may necessitate the interconnection of several amplifiers. The most usual situation would be
the attachment of extra slave amplifiers to a mixer amplifier in order to increase the available power output whilst delivering the
same program. This is made possible by linking the appropriate mixer facility socket pin (pre or post master gain where available)
of the mixer amplifier to the input pin of the slave amplifier(s). The cable should be single conductor screened, and the braid/shield
connections should also be made between the appropriate pins. See Fig. 7 for clarification.
NOTE: This is the only means of interconnection that is permitted. It is most inadvisable to attempt to combine the loudspeaker
outputs of several amplifiers into one loudspeaker feed line. At the very least, severe problems, and most likely serious damage
will result.
The loudspeaker system should always be planned such that it is divided up into sections, each of which will be powered by just
one amplifier output section.
Page 13
MACRO range installation manual. Issue 6
Fig. 7 Interconnection of several amplifiers
POWER AMPLIFIER MODULE
The power output stage of the amplifier including all low level drive circuitry, and output devices are contained in a module which
is bolted to the rear panel by four screws. The module is connected into circuit by push-on tab connectors facilitating easy change
of a suspect module. The module may be unbolted and swung out to enable circuitry to be worked on with power connected,
though as the heatsink is no longer coupled, the module should not be driven into a load for any length of time. Output devices are
mounted on sockets so they may be replaced without dismantling the PCB from the heatsink plate. See Fig. 8
Adjustments
There are three pre-settable adjustments on the power output module which are accessible from the top of the
amplifier. When received from the factory, the amplifier will have been adjusted for correct overload protection, output device
biasing, and input sensitivity, and no further adjustment will be necessary. The recommended adjustments are:
OVERLOAD: Top left of module when viewed from front: Set for triggering at full amplitude on a load of 3 x rated output.
OUTPUT DEVICE BIASING: Centre top of module: Set nominally for a total module drain of 200mA, measured via the supply
push-on tab.
INPUT SENSITIVITY: Top right of module: Set for 0.775V RMS at 1kHz.
The above adjustments necessitate the use of certain test equipment and facilities, and the precise methods are outside the
scope of this manual. The adjustments may be identified by referring to Fig. 8
The front panel ‘error’ LED is energised for a minimum period of 1.5 sec. when an output overload condition is detected. During
this time, the signal drive to the output stage is suppressed.
The detection circuit and LED will remain energised for the entire duration of any such overload, and the amplifier will return to
normal operation 1.5 second after removal of the overload. Note therefore that this circuit will not register an overload until a
suitable signal is present.
LOUDSPEAKER OUTPUT
The amplifier is designed to work primarily with 100V line loudspeaker systems. Facilities are also provided for 50V line and low
impedance loads. IT IS ESSENTIAL to provide the correct loudspeaker load for safe and distortion-free reproduction.
When connecting a MACRO mixer amplifier or slave amplifier onto an existing loudspeaker network, the load should be ascertained
by measuring the load by a proprietary impedance bridge
The cover provided on the output barrier terminals is a safety cover and should be retained. Access to the terminals is gained by
Page 14
MACRO range installation manual. Issue 6
Fig. 8 Power amplifier module fixings and adjustments
removing the 4BA nut on the left and lifting that end clear of the stud. The cover may now be swung round.100V output
The general concept of a 100V line loudspeaker system is that a quantity of 100V line loudspeakers are connected in parallel
across the amplifier output terminals. The loudspeakers may be arranged in any order, any combination and if necessary, using
any number of feeds from the amplifier. They may be grouped onto sub-circuits which may then be controlled by switching or
group volume controls, etc., as required to suit the operational requirements of the system. Sub circuits may be dedicated to
‘Page-only’ operation and switched in by means of relays powered by the comprehensive MACRO current sinks. See APPENDIX
C for typical arrangements.
The 100V line loudspeaker output terminals will deliver conventional full program content, i.e. all music and all paging/priority
signals. For 100V line loads connect between the two outer terminals and for 50V line systems connect between the centre and
right terminals.
All three 100V line output terminals fully floating, earth-free, and centre-tapped. This latter is useful in certain critical installations
where careful balancing of the loudspeaker network may be necessary. The terminal marked ‘CT’ may be earthed to chassis if
required.
Low impedance output
Power output to the loudspeaker load may be taken at low impedance (low Z) The terminals marked A-O-B present a very low
impedance output across A-B and which is centre-tapped at O. These terminals are not specifically rated, but as a guide, the
output impedance across the A-B terminals is in the order of 2 ohms. The centre-tap is a direct connection to 0V level (chassis,
signal earth, and -24V).
Typical loudspeaker load arrangements
The following are acceptable examples of loudspeaker loading arrangements:
A
B
C
400 x 1/2 Watt 100 Volt line speakers = 200 Watts total load to the amplifier. Use a 250 Watt amplifier
200 x 1 Watt 100 Volt line speakers = 200 Watts total load to the amplifier. Use a 250 Watt amplifier
2 x 50 Watt 100 Volt line speakers = 100 Watts total load to the amplifier: Use either a 100 Watt amplifier (or a 250 Watt
amplifier to allow for 150 Watts future development).
D
E
F
12x 5 Watt 100 Volt line speakers = 60 Watts total load to the amplifier, and therefore 40 Watts spare capacity for future
expansion if using a 100 Watt amplifier
10 x 5 Watt, and 6 x 2 Watt 100 Volt line speakers = 50 + 12 Watts = 62 Watts total load to the amplifier. Use a 100 Watt
amplifier.
4 x 60 Watt units each tapped at 30 Watts, and 20 x 4 Watt units tapped as follows: 5 @ 4 Watt, 5 @ 2 Watt and 20 @
0.5 Watt 100 Volt line speakers = 160 Watts total load and therefore 90 Watts spare capacity for future expansion or
for final adjustments. Use a 250 Watt amplifier
See APPENDIX C for typical loudspeaker arrangements.
Page 15
MACRO range installation manual. Issue 6
AUXILIARY OUTPUT CONNECTION
A standard 25 way ‘D’ connector on the amplifier rear provides all the auxiliary connections associated with current sinking,
alarms, auxiliary DC and signal outputs, etc., where applicable. The standard connections are as follows:
1
2
3
4
5
6
7
8
250mA current sink activated by input module No.1 during priority access
250mA current sink activated by input module No.2 during priority access
250mA current sink activated by input module No.3 during priority access
250mA current sink activated by input module No.4 during priority access
250mA current sink activated by input module No.5 during priority access
250mA current sink activated by input module No.6 during priority access
250mA current sink activated by input module No.7 during priority access
250mA current sink activated by input module No.8 during priority access
250mA current sink bus activated by any module gaining priority access
250 mA CDM current sink bus activated by any module with this feature
0Vforgeneral purpose
9
10
11
12
13
Nominal 24V+ DC unregulated output, for use with current sinks
Mains power input failure
alarm contacts - normally open
14
15
DC power input failure
alarm contacts - normally open
Notes:
a)
The current sink connections originate on
16
17
18
19
individual modules. These current sinks are unfused
and can carry a maximum of 250mA from a positive
(+ve) source.
process/equaliser control
for future use.
b)
The pin 12 connection originates from the pre-
20 nc
21 nc
22 nc
23
24
25
amplifier stabiliser module (PS.9 etc.) where a F1A
fuse is located - see APPENDIX E
c)
The ‘fail’ alarm connections are ‘open’ when
50V
0
50V
duplication of
100V loudspeaker
output terminals
the unit is de-energised, and closed during normal
powered operation.
Priority controlled DC current sinks
This unusually comprehensive feature is rarely found on general purpose amplifiers but is useful in microphone paging or alarm
systems where a number of operations may be required co-incident with the use of the priority facilities, e.g.
a)
b)
c)
The introduction of ‘page only’ 100 Volt loudspeaker circuits by using relays to switch them on only during paging.
The restoration to full volume of a remote 100 Volt loudspeaker group volume control, such as the Mustang MVC series.
The powering of lamps at a microphone position, to indicate that the amplifier priority system is already in use (by an alarm
tone generator for example)
d)
e)
f)
The interruption by means of a relay of the sound output of another amplification system.
The sending of a low-level paging signal by means of a relay, to another remote amplification system
Control of a designated loudspeaker zone control unit from the Mustang ZC or MC ranges.
The principle of operation is that when the signal priority circuit of any of the input modules is activated, the associated DC current
sink is operated and the associated terminal of the Auxiliary output connector - becomes a 0 Volt point. This is used to complete
a simple external circuit comprising relays or lamps etc., connected to the +24V DC terminal.
Terminals 1-8 are individual sinks controlled individually, whilst terminal 9 is activated whenever ANY of the individual sinks is
operated.
The current sinks are polarity protected for use in positive (+ve) applications up to 40V. DO NOT ATTEMPT to pass more than
250mA.
NEVER connect the +24V and current sink connections directly together - serious damage to the module will result. In the off state
there is effectively no connection.
See APPENDIX B for typical applications of the Auxiliary Output connections.
Chime duration monitor sinks - (CDM)
This facility is provided on those modules which feature a chime generator. The sink output lasts for the duration of the chime
tones (which are triggered on priority access) and the the individual sinks are connected to a sink ‘bus’
so that a lamp may be energised on a paging microphone to indicate at which point to commence speaking. This connection is
unfused, and is limited to 250mA from a positive (+ve) source. See APPENDIX B for typical application.
100V line output
This is an extension of the rear 100V loudspeaker output barrier terminals to facilitate all connections to be ‘pluggable’ if required.
24V DC supply
The 24V+ terminal of the Auxiliary output connector provides an unstabilised DC supply, which is limited to 1 amp by an internal
fuse on the pre-amplifier stabiliser module (see APPENDIX E) and the return is via the 0V terminal. This feature would normally
be used with the DC current sink.
Page 16
MACRO range installation manual. Issue 6
COMBINING THE INPUT/OUTPUT FACILITIES OF TWO OR MORE UNITS
This may be considered where one single amplifier cannot provide enough input facilities or output power for a particular application.
Mixers may be combined with mixer amplifiers, and with slave amplifiers in any combination via their respective mixer facility
sockets.
Example M2508 and M250 to provide 8 inputs and 500 Watt output to two loudspeaker zones. Interconnect using pins 3 of each
mixer facility socket.
Example M2508 and two M100 to provide 8 inputs and 450 Watt output. Interconnect using pins 3 of each mixer facility socket.
Example M8/M and M1008 to provide 15 priority inputs and 100 Watts output capability. Fit an L.25 module in input 1 of the
M1008 and drive it from the mixer facility output of the M8/M. Connect the ‘ANY’ sink of the M8/M to pin 5 of the input No.1 M1008
such that any priority operation of the M8/M seeks access to input No.1 M1008 as though a normal input. All individual sinks on
either unit will still be relevant. The mixer facility of M1008 may be used to drive slave amplifiers in the same system if required.
See Fig. 9 for clarification.
NOTE
The loudspeaker system should always be planned such that it is divided up into sections, each of which will be powered by just
one amplifier output section.
It is most inadvisable to attempt to combine the loudspeaker outputs of several amplifiers into one loudspeaker feed line. At the
very least, severe problems, and most likely serious damage will result. Whilst it is technically feasible, the risks faced will render
it an impractical option. For clarification, consult the System design department of Mustang Communications Ltd.
POWER SUPPLY
AC Mains power input
A standard IEC 3 pin mains connector is supplied with each MACRO amplifier. It is essential that the Earth connection is made
properly, as the chassis of the amplifier is earthed via this facility. The mains power required is 230V to 240V AC at 50-60Hz. If
a slightly lower voltage is used, then the battery charging facility (if fitted) may be impaired.
The power requirement for the amplifier, even when used at full power, is minimal and should be taken from the AC mains supply
via a 3 core flexible cable. It is vital that the connections to the mains input line socket are made to the correct terminals. The
connections are:-
L
N
E
Live
Neutral
Earth
DO NOT operate the amplifier under any circumstances without an electrical earth connected. This is a permanent safety earth.
DC power input (if applicable)
Certain models in the MACRO range are designed to operate from 24V DC during periods of mains supply failure. It is permissible
for this voltage to vary between 20V and 28V without undue problem, though the battery charging capability will vary accordingly.
A style MS.62 military style connector is supplied with each amplifier, and the corresponding connections are printed alongside the
panel connector, as follows;
Pin A
Pin B
Pin C
+24V
Chassis
- (0V)
Important: If either positive or negative terminals must unavoidably be earthed, it is preferable that it be NEGATIVE. Note that the
DC connections are not totally free of earth, as the signal earth and DC (-) of the amplification are connected to chassis by a 220
ohm resistor.
Any conflict of DC earthing is likely to result in severe damage to the module printed circuit tracks should incoming circuitry be
earthed too.
Systems powered by both AC and DC supplies
Systems utilising several MACRO amplifiers to be powered from both AC and emergency DC supplies should be connected such
that the AC is supplied by the routine mains supply - for normal operation, and upon failure of this, the DC is supplied from an
emergency DC battery system with integral charging circuitry. The internal MACRO battery charger circuit should be disabled
(see below).
For clarification see Fig. 10
Main ON-OFF front panel switch
For mains powered MACRO equipment (or non standard DC only units) a two pole switch is used. Mains powered units are
switched in the Neutral and Live connections. DC units are switched in the +ve DC input connection only.
AC Mains/DC equipment utilises a three pole switch which combines both the above functions.
Due to the very high inrush current of an AC mains/DC powered MACRO amplifier, a time lapse circuit and holding solenoid are
employed. The DC section of the power switch therefore carries minimal current. This is not a feature of mixer units.
If a loaded slave amplifier is subject to an input signal during the switch-on sequence using only the DC input, the resulting drain
on the time lapse circuit may prevent the holding solenoid from operating properly.
Page 17
MACRO range installation manual. Issue 6
Fig. 9 Priority connections for multiple amplifier systems
Page 18
MACRO range installation manual. Issue 6
The front panel of the power switch may be removed by light leverage to enable lamp replacement. Power for the lamp is derived
from a small 18V stabiliser on the Power Management Board.
Failure to illuminate will indicate one of the following:-
a)
b)
c)
d)
Lamp failure
Neither AC nor DC power to the amplifier
Both AC mains and DC fuses on the rear panel have failed
Stabiliser circuit has failed
‘ERROR’ status indicator LED
Illumination of this LED is as a consequence of the overload protection circuit in the power output module being triggered.
This could be as a result of the following:
a)
b)
c)
A severe overload on the loudspeaker line
Transitory saturation of 100V line loudspeaker transformers connected to the 100V line terminals.
An electronic fault in the power output module drive circuit.
Illumination resulting from a) or b) will occur only whilst an audio drive signal is present. During periods of illumination the amplifier
output will be muted and minimal current will be drawn from the power supply. This condition can be maintained indefinitely
without further risk to the amplifier.
‘POWER’ status indicator LED
A three colour LED is used to indicate the integrity of AC and DC power supplies:
Green
Red
Orange
AC supply connected
DC supply connected
AC an DC supplies connected
Power supply failure monitoring
The ‘Auxiliary’ output D connector provides the facility to monitor the integrity of both the AC mains and DC standby supplies. Each
supply energises a relay with light duty normally open contacts which are taken to pins 13/14 and 15/16. The relays are located
Fig. 10 AC & DC supply connections and monitoring
Page 19
MACRO range installation manual. Issue 6
on the Power Management Board and will drop out as a result of :-
AC:
DC:
AC supply failure
AC fuse failure
AC supply disconnection
Amplifier switched off
Rectifier circuit failure
DC supply fuse failure
DC supply disconnection (even with charger operational)
DC standby supply failure
Amplifier switched off
These relay contacts may be used to trigger remote audible or visual alarms within the system to draw attention to a possible
problem.
Power supply change-over
This function is carried out automatically and instantaneously upon failure of the regular AC mains supply. There is no break in
service and all facilities are retained (except battery charging), for the duration of the condition. Upon reinstatement of the AC
supply, the amplifier automatically reverts to AC operation and battery charging re-commences.
The change-over process may be monitored by making use of the power supply failure monitoring relay contact mentioned above.
See Fig. 10 above, for clarification.
Battery charger circuit
Units except mixers provide trickle charge facilities for use with standby batteries connected to an AC mains/DC amplifier. Output
is in the form of a 0.5 second pulse at 1 second intervals and is controlled from the Power Management Board, (PMB.1, etc.). Low
AC mains input supplies will adversely effect the charge rate.
If, however, the charging facility is not required - perhaps because the battery system provides its own dedicated charger - then it
is preferable to disable the amplifier charger by cutting the red wire link at the end of the heat-sink type power resistor attached to
the Power Management Board heatsink plate. See APPENDIX D for identification of this link.
EARTHING AND HUM LOOPS
In all systems it is possible to inadvertently set up a hum loop. Each manufacturer has different methods of earthing his equipment
and so lack of familiarity with them may result in problems. A loop will manifest itself as a low level soft hum at either 100Hz or
50Hz which is not generally effected in tonal or amplitude content by any user or adjustment controls. There are many potential
earth loop paths in any system, but the larger the system, the more they are compounded, and resolving the problem can be
extremely exasperating unless a disciplined and logical approach is used.
Each system must be considered separately although rules of thumb do apply. Generally an audio loop will be set up wherever
two points in an audio system are interconnected by two earth paths. The resulting circuit will act as a ‘turn’ in a transformer, with
any stray magnetic fields setting up resultant electrical currents in it. These currents are superimposed on whatever currents are
intentionally there, and these may be very low level audio signal currents.
However, the electronic circuitry within the chassis is earthed to chassis independently of the electrical safety earth by means of
a wire link or a 220 ohm resistor - dependent upon the unit - adjacent to the mixer facility socket. This provides earthing to prevent
self-oscillation whilst avoiding any tendency to cause earth loop problems. (See also the preceding sections covering the ‘Mains
power input’ and ‘DC power input’ requirements).
In designing the MACRO system, we have borne in mind that the applications for the equipment will generally be in large scale
installations where there may be many conflicting requirements. Therefore MACRO amplifier chassis are always earthed via the
power input connections.
********* THIS IS A SAFETY EARTH AND MUST NEVER BE DISREGARDED. ***********
Particular care should be taken when terminating the Locking DIN input plugs, as the cable clamp will connect with the plug body
on assembly and thence with the amplifier rear panel on insertion. Thus, if the signal cables’ audio screen is connected both to the
clamp and to pin 2, a loop will result. Similarly with the mixer facility connector. Aim to earth each amplifier fully in one place only,
with interconnection of amplifiers or ancillary equipment via input modules featuring transformer input circuitry, - for example L.24
to L32. These may be wired in a fully floating mode thus providing full isolation. Connect the audio screen of a signal cable to a
signal earth at one end only.
Bear in mind, also that with DC powered systems, the signal earth of each amplifier will be connected to the -ve terminal of the DC
supply. If that is already unavoidably earthed, it dictates that it must be the central earthing point of the system.
FACTORY FITTED OPTIONS
TB/ALC
TB/S
MAC/LT
Automatic audio level control (ALC)
Loudspeaker line surveillance facility
Balanced line input for slave amplifiers
Free-standing cased units - specified only for earlier models. Originally Mustang product code FS.3U
Current amplifiers specified as rack mounting or free-standing.
A wrap-round sleeve case can only be factory fitted to a MACRO unit. A rack mounting unit, once shipped, cannot be fitted with
such a case due to the design of front panel being different for rack and free-standing versions.
Page 20
MACRO range installation manual. Issue 6
Automatic level control - all units except slave amplifiers. Mustang product code TB/ALC
The standard module fitted to a mixer or mixer-amplifier to provide line driver facilities is a TB.6 and is located second from the
right when viewed from the front. This is replaced with a TB.6A to provide the Automatic level control facility (ALC) and it will
enable the system to be set up such that a pre-settable amplitude cannot be exceeded. All signals that would normally pass
through the amplifier circuitry are subject to automatic level control operation.
The module operates to produce a fast “attack” so that limiting to a pre-determined level takes place almost instantly, and a slow
“decay” whereby the sensitivity - or gain - is allowed to increase progressively over several seconds or until another limit is
triggered.
To set the module to give the required performance: Firstly, referring to APPENDIX E, identify the ‘GAIN’ pre-set control which is
adjacent to the integrated circuit at the left of the board approximately half way up. Then identify the ‘THRESHOLD’ pre-set control
which is a little below it. Set the Master Level control on the mother PCB to maximum (see Fig.1 on page 7). Set the GAIN pre-
set fully anti-clockwise to give approximately unity gain. Now, whilst running the amplifier at full volume using a test signal, adjust
the THRESHOLD to the desired maximum output level indicated by the output meter. Clockwise adjustment increases the
threshold level. The threshold is adjustable from -24 dBM to +8dBM.
The module will now be operating as a limiter. To enable the Automatic Level Control aspect, the GAIN control should now be
adjusted clockwise until sufficient gain is available to enable the lowest level input signal to attain the THRESHOLD.
The ALC facility will have been specified where -
a)
b)
c)
The amplifier output is required to be limited to prevent clipping distortion;
The average sound level is to be limited to a specific audible level;
Inductive loop systems which may be unattended though still need to operate to the requirements of the current
legislation.
As supplied by the factory, GAIN is set to 0dB (unity) and the THRESHOLD control is set to maximum, and therefore no effect will
initially be apparent. See APPENDIX D to locate the module, and APPENDIX E for identification of the adjustments.
Fig. 11 Balanced line input connections
Balanced line input for M/100 and M/250 slave amplifiers. Mustang product code MAC/LT
This option would normally be fitted where difficulty may otherwise be experienced with hum/earth loops. The input signal circuit
has no earth connection, and is referred to as being “fully floating”.
Page 21
MACRO range installation manual. Issue 6
The Locking DIN pin connections are:-
Pin 1
Pin 2
No connection
out of phase audio
.775V RMS @ 10k ohms
balanced (floating)
Pin 3
in phase audio
It would normally be appropriate to interconnect two pieces of equipment using twin-screened cable. The braiding should be
earthed to one unit only. If the decision is made to use the Mustang power amplifier for earthing, then the cable clamp of the DIN
plug may be used for the purpose, without the likelihood of a hum loop.
As this is a fully floating input facility, either single or twin core screened cable may be used. This will depend upon the specification
of the equipment supplying the input signal.
The input impedance of balanced input slave amplifiers is 10k ohms.
See Fig. 11 for further clarification.
Line surveillance. Mustang product code - TB/S
The standard module fitted to a mixer or mixer-amplifier to provide line driver facilities is a TB.6 and is located second from the
right when viewed from the front. This is replaced with a TB.6S to provide the Line surveillance facility, which, in the MACRO
system is carried out by injection of an encoded supersonic tone into the audio signal path at the line driver stage. The presence
of the current which this signal induces into the loudspeaker line is subsequently monitored externally for deviation from a pre-set
level.
The amplitude of the injected signal is adjusted using the pre-set potentiometer at the top right hand corner of the TB.6S (viewed
from component side - see APPENDIX E). Turning the control clockwise will increase the level of injection. The correct factory
setting is such that 2V is the amplitude of the signal appearing across the fully loaded loudspeaker output terminals at the amplifier
rear. Useful re-adjustment of this control can be accomplished only with the aid of an oscilloscope of suitable bandwidth. The
same level applies in the case of MACRO systems incorporating mixers and slave amplification. See APPENDIX D to locate the
module, and APPENDIX E for identification of the adjustments. Adjustment of the modules treble or bass controls will not effect
the surveillance injection. Do not attempt to alter the ferrite cored inductor of the injection circuit.
The loudspeaker current monitoring function as mentioned above would be facilitated by using a MACRO SL/10 unit.
INSTALLATION
Selection of signal input cables
It is essential that input connections are made carefully, using appropriate screened cable, soldered to DIN connector plugs, and
using the appropriate terminal numbers indicated in the section describing the input modules in this manual. Unscreened “telephone”
type cables are NOT suitable. Either twin conductor, or single conductor types may be used depending upon the application. For
long fixed cable runs, a cable with a conventionally braided outer shield is preferable to a lap-screened type. A conductive plastic
shield type is ideal for cables which will be subject to constant flexing such as those connected directly to microphones. Failure to
meet these requirements will result in inferior performance, and at worst, damage to the amplifier.
It is not possible in this manual to be specific about the exact types of input cable for use in any particular amplification system, as
many practical factors will need to be taken into account. However, as a guide, we would recommend the following:
Balanced lines should be wired in twin, twisted core, screened cable with a conductor size of at least 0.22sq.mm., and preferably
0.5sq.mm. This is equally valid for dynamic or phantom-powered microphones, and line inputs.
Paging microphone lines will need an extra two conductors to operate the priority circuit of the amplifier. These need not be
screened. For short runs, (up to 2 Metres), paging microphones may be connected using 4-core overall screened cable, and for
longer runs, (up to 10 Mtrs), 4-core individually screened cable. If it is necessary to run a cable over say 10 Mtrs, then there may
be some performance advantage in using a separate twin-twisted screened cable for the audio, and a separate twin unscreened
cable for the priority operate cores.
Line level cables, such as those between a tape recorder and the amplifier, which may be up to a few metres in length are less
critical and may be run using lap-screened, single or twin cable with conductors of 7/0.1mm or 7./0.2mm.
Selection of loudspeaker cables
Use of an appropriate cable for the connection of loudspeakers to the amplifier will ensure that a minimum amount of audio power
is lost during transmission to the loudspeaker network. The loss will depend upon several factors - loudspeaker loadings, size of
cable conductor, length of cable, etc.
As a general rule, for any particular loudspeaker system, the longer and the thinner the cable, the greater will be the loss. We
therefore recommend, that the system is planned such that the amplifier is as near as possible to the loudspeakers, and that the
cable used is as large as practicable.
Mineral insulated cables may be used without problem.
Either solid or flexible conductor cables may be used, or a combination of both. It would be appropriate for a heavy duty cable to
be used between the amplifier location and the general loudspeaker location - carrying the full load, and for the subsequent
loudspeakers of the network to be interconnected with thinner cable.
Fitting Locking DIN connectors
Signal input connections are made via a locking DIN 5-pin plug (Mustang Code 5-180). To insert:- rotate the plug until the pins line
up with the corresponding socket contacts, and push fully in. Rotate the locking ring clockwise to secure. Similar plugs used for
domestic Hi-Fi systems may be used though they are generally of inferior quality, and have a weaker cable clamp with no locking
facility.
When connecting the input cables to the locking DIN plugs, it is most important to observe the following:-
Page 22
MACRO range installation manual. Issue 6
A.
DO NOT allow the cable braiding/shield to contact the cable clamp, plug body or fixing screw. An earth/hum loop
will result. This topic is fully covered on page 20.
B.
C.
Application of silicon grease to the cable outer sleeve will facilitate easy insertion into the grommet.
Be careful when soldering. Avoid bridging adjacent pins of the locking DIN connectors with solder. If pins 4 and
5 are not to be used, break them off to provide extra space for soldering.
Siting
The position chosen for installation of the amplifier will depend upon many individual factors outside the scope of this manual.
However, the amplifier should be positioned as close as possible to the loudspeaker network, to minimise losses. Ideally, loudspeaker
cables should be routed separately from sensitive microphone cables to avoid the possibility of spurious coupling and resultant
oscillation. Please also refer to the following paragraph on ventilation. Choose a position where there is little likelihood of any
liquid being spilled on the amplifier.
Ventilation
Individual mixers and amplifiers in the MACRO range develop very little heat when switched on and not in use. M8/M and M8/MD
units develop virtually no heat in use and need minimal ventilation. Mixer amplifiers and slave amplifiers develop moderate
amounts of heat dependent upon the amount of sound power delivered to the loudspeaker loads. The design of these amplifiers
is such that heat is conducted from the rear panel across the whole of the chassis which is in effect a very large heatsink and
designed to dissipate the heat by convection. However, in order to do this the amplifiers needs ventilation space at least at the
rear and sides. Rack mounting amplifiers in irregular or spasmodic use may be stacked as required provided that there is
sufficient free flowing air at the rear.
If several 250 Watt amplifiers, are mounted in a rack, and used in a demanding application e.g. alarm tone generation, continuous
full power music, etc., then it is likely that the heatsink temperature will exceed 100 degrees centigrade at which temperature
certain components will start to be thermally stressed. This can be inconvenient (or dangerous in an alarm generation system)
and consideration should be given to spacing the amplifiers. A 1U space should be provided between every second amplifier, and
for systems over 400 Watts, forced ventilation should be considered. Mustang FP.2S or FP.2B fan panels and corresponding
ventilation panels may be specified. The amplifiers’ naturally long operational life may be realised by a cool operating environment.
To summarise, if MACRO amplifiers are to be used at high power levels DO NOT:-
A)
B)
C)
D)
install in small enclosed spaces
stack in rack cabinets without adequate cooling, spacing, or ventilation
install above radiators or near heaters
block-in side and/or bottom surfaces
Interference
Steps have been taken in the designs of the range to minimise interference from external sources. The main possibilities would
be -
a)
b)
c)
d)
e)
f)
faulty or insufficiently suppressed lighting dimmer
incorrectly shielded or earthed lighting dimmer
lighting dimmer lines close to signal input lines
strong radio/TV transmission immediately adjacent
faulty fluorescent tubes or tube fittings
unsuppressed heavy electrical contacts
stray magnetic fields from other mains equipment adjacent
computer, calculator, or related equipment adjacent
g)
h)
The source of interference should be established by elimination and logic, and equipment repaired or modified accordingly, rather
than attempting modifications to the amplification equipment.
Removal of control knobs
Mixer and mixer-amplifier units are fitted with removable control knobs to deter tampering. Remove simply by pulling firmly away
from the front panel. The knobs are of the collet type, and will disconnect the splined spindle from the potentiometer inside the
chassis. The panel holes may be plugged using the blanking plugs supplied. They are a push-clip fit and cannot be removed from
outside the amplifier. The knobs and spindles may be replaced at any time.
Checklist
During the commissioning of the amplifiers in the MACRO range, various options are available to the engineer to enable him to
meet various technical requirements and the operating requirements of the user:
Use of priority or passive operation for input channels
Priority control out to remote relays, lamps, etc.
Individual input module sensitivity adjustment
Bass cut on microphone input module
Timer setting of tone generator modules
Pre-announcement chime level
Optional auto level control adjustment (ALC)
Control knobs to be removed
Page 23
MACRO range installation manual. Issue 6
FUSES
Fuses for the protection of both the AC and DC supplies are located on the rear panel.
Certain fuses are contained within the chassis of MACRO equipment rather than on accessible front/rear panels:
(A) F1A pre-amplifier DC fuse on the pre-amplifier stabiliser module
(B) F1A auxiliary DC fuse on the pre-amplifier stabiliser module
(C) Special fusible link on the power output module
See APPENDIX D and APPENDIX E for identification.
Failure of the top fuse (a) could indicate a problem in the stabiliser module or within the subsequent mixer circuitry. The lower fuse
(b) protects the Auxiliary +24V DC output (pin 12 of the ‘D’ connector). It is rated at 1 Amp and if this supply is used to source
current for the priority current sinks transistors, then these may have been damaged by the overload. These sinks are located on
each priority module.
The failure of fuse (c) would indicate that the power output module has been seriously damaged. Output transistors and associated
driver transistors may have failed, so simple fuse replacement is therefore inadvisable.
If a fuse blows repeatedly, a fault is indicated. Do not attempt to force the amplifier by fitting larger fuses. All standard fuses
should be replaced as a matter of routine every year if in regular use.
When replacing fuses, disconnect the mains supply and allow a few minutes for capacitors to discharge.
REPAIRS AND MAINTENANCE
Should components be required for replacement purposes, these may be obtained without delay from the address on the cover of
this manual. It would be preferable to use original specification components rather than improvise or modify the amplifier.
The MACRO range of amplification has been planned so that servicing and maintenance is extremely uncomplicated. All main
potential sources of failure are either pluggable or accessible from the top of the main circuit board. It is unlikely that the main
board will ever need to be removed except for the removal of spilled liquid, or broken mechanical parts. The following information
is a procedural guide for the most likely problems.
Free standing case removal
Free standing cased amplifiers are dispatched with the case fitted and to make any internal adjustments or module changes it will
be necessary to remove it. Turn the amplifier upside-down on a clean soft surface to avoid scratching and remove the four outer
cross-point headed screws. Revert the amplifier and using strong finger pressure, push out the bottom flanges at both sides of the
case, and slide it upwards over the chassis. Replacement is a reversal of this process. Line up the holes in case and chassis
before attempting to re-fit the screws. Use the correct size of screwdriver.
The case is manufactured from PVC clad aluminium and therefore, whilst being washable it will not withstand any direct heat, i.e.
cigarettes, soldering irons etc.
Removal of main pre-amplification circuit board
Remove the gain control knobs and associated spindles by pulling firmly. Remove all the modules. Spring in the 8 plastic support
pillars, spaced along the board. By lifting the rear edge of the board it will now be possible to push to board backwards and
upwards giving access to the bottom of this board. De-solder the signal cableform if complete access is required.
WARRANTY
This amplifier should operate successfully for many years if installed correctly. However, should any fault occur within 24 months
of installation, irrespective of usage or application, the manufacturer undertakes to replace parts, or the whole unit, at their
discretion, free of all labour or parts charges. However, should investigation of such a fault indicate operation of the unit outside
its specification, then the manufacturer reserves the right to levy an appropriate repair charge.
Should a fault be suspected, your dealer should be notified in the first instance. All returns should be made via your dealer,
forward carriage paid, and be accompanied by details of:
a the reported symptoms
b brief details of the installation.
c details of the circumstances of failure
Following the routine warranty period, Mustang amplifiers may be returned via your dealer, to the manufacturer for any necessary
repairs or refurbishing. Details of the work required/reported fault must accompany the unit, and nominal charges will be levied.
Page 24
MACRO range installation manual. Issue 6
FAULTS - SYMPTOMS AND CHECKLIST
The following list of fault symptoms and check points cannot be considered as comprehensive, but as a guide to the most likely
faults and causes. We assume that the input sources and loudspeakers are properly connected and in good working order. Be
sure to check these carefully first before investigating the amplifier.
FAULT SYMPTOM
CHECK ILST
1
2
Sound off, main power switch lam opff
Sound off, main power switch la pmon
AC mains fuse, mains lead, mains power, mains switch. DC supply, fuse, or le das.
Internal AC/DC power fuses, output transistors, input connections, module edge connect tos,
output transformer continuity, pre-amplifier stabiliser module, line driver module, priority channel
not being triggered, input module not being set by dedicated jumper pins, input module being
muted by operation of higher priority.
3
4
Sound f iant
Module sensitivity adjustment, incorrect output connections, overload on mixer facility soc ekt,
incorrect input pin selection, incorrect choice of input module.
Sound loud but disto tred
Incorrect choice of input module, incorrect module sensitivity setting or pin selection, incor er ct
loudspeaker load, volume control too far advanced, system requires amplifier of greater power
or more efficient loudspeakers, master control set too low.
5
6
Sound distorted on bass p aeks
Sound distorted an ldow
Bass controls too high, poor quality 100V line loudspeaker transformers. See also No.4 ab voe.
Incorrect choice of input module, incorrect module sensitivity setting or pin selection, incor er ct
loudspeaker load, partial loudspeaker line short, output transformer short circuit, master control
set too low.
7
8
Case gets ver hyot
Incorrect (excess) loudspeaker loadings, see page 18, parasitic oscillation (usu laly
accompanied by soft hum and mild distortion and appears and disappears at a certain treble
control setting) see 8 below, insufficient ventilation, see page 31
Parasitic/supersonic oscilla iton
Insufficient screening on high sensitivity input signal cables, insufficient earth ni g,
loudspeaker/input leads adjacent or parallel for some length, unloaded input line, incoming
parasitic on signal line from ancillary equipment, braiding on input cable disconnected or
intermittently faulty.
9
Soft hum - volume controls odwn
Earth/hum loop - see page 25, power supply capacitor failing, induced magnetic field rfom
nearby mains equipment.
10
11
12
Hum
iHss
Incoming hum from ancillary equipment, induced hum on sensitive input cables, incor er ct
earthing to amplifier or ancillary equipment, earth/hum loop, see page 25
Excess treble, signal noise incoming from ancillary equipment, unloaded input signal line, noisy
input module.
iFzz
Interference from lighting dimmers, dimmer lines, faulty fluorescent lights, earth/hum loop, see
page 25
13
14
Loud hars hum
Disconnected signal input braiding, or buzz earth/hum loop, see pa eg 25
Intermittent loud crac ikng
Strained input module edge connectors, dirty edge connectors, intermittent input el ad
connections, dirty voltage selector pins, dirty mains plug pins, loose mains fuse, radiated
interference from thermostat etc. see also No.5 above.
15
16
17
Howling or ringing and boo imng
DC fuses blo iwng
Acoustic feedback between microphone and loudspea ekrs
Failed output transistors and/or driver b aord
Mains line fuse blo iwng
Mains switch suppressor shorted, main rectifier failed, mains transformer failed, ou pt ut
transistors failed
18
Input channe ol ff
Incorrect priority triggering, module edge connector, module muted by higher priority, i pnut
signal fault, module not set to passive mode
19
20
Incorrect signal prio irty
Intermittent s uond
Incorrect setting of PCB priority switches or of priority/passive jum eprs
Strained input module or driver board edge connector, fractured input cable, worn volume con rtol
track.
21
22
23
24
25
Mixer AC supply fuse blo iwng
Power switch u lnit
Regulator mo udle
AC (and/or DC) power missing, switch lamp, internal lamp regulator, power fu ess.
Signal bass peaks triggering protection infrequentlycircu tiry
Loudspeaker load excessive, or faulty threshold frequently sett ni g.
Faulty power section module.
ERROR lamp flashing infreque tnly
ERROR lamp flashing freque tnly
ERROR lamp on permanently, no a duio
output
26
Rhythmic clic ikng
Incompatibility of internal charging system and earthing in multi-amplifier installation, red wi er on
Power Management PCB not disconnected
Page 25
Appendix A
MACRO range installation manual. Issue 6
Appendix B
MACRO range installation manual. Issue 6
Appendix C
MACRO range installation manual. Issue 6
Appendix D
MACRO range installation manual. Issue 6
MACRO range installation manual. Issue 6
Appendix E
|