Australian Monitor. SY 6125, SY 400, SY 400V, SY 800V, SY 1200 User Manual

Professional Audio Amplifier

SY 400

SY 800
SY 1200
SY 1600

SY 400V
SY 800V

SY 6125
SY 4200

Operation Manual

IMPORTANT!

Please read carefully.

This operation manual contains important information
regarding safety precautions, installation, performance,
operation and maintenance of your Synergy-Series power
amplifier. You should familiarize yourself with the contents
of this manual operating your amplifier.before

Safety Precautions

and Labelling

The rear panel of this amplifier has a number of
markings and internationally recognized symbols
relating to the hazards and precautions that should
be taken when operating MAINS connected
equipment.

The presence of a LIGHTNING FLASH with an
arrowhead contained within the boundaries of an
equilateral triangle is intended to alert the user that
dangerous uninsulated voltages may exist within the
amplifiers enclosure. These voltages may be of a
sufficient magnitude as to constitute the risk of an
electrical shock.

This symbol is reinforced with the text:

!CAUTION!

RISK OF ELECTRICAL SHOCK

DO NOT OPEN

The presence of an EXCLAMATION MARK
contained within the boundaries of an equilateral
triangle is intended to alert the user that there is
important operating and maintenance literature that
accompanies the amplifier.

REFER SERVICING TO

QUALIFIED PERSONNEL.

NO USER SERVICEABLE

PARTS INSIDE.

The user should not attempt to service the amplifier.
Only qualified and knowledgeable personnel familiar
with the internal workings of the unit should attempt
any repair, servicing or authorized modificationto the
unit. The unit does not contain any parts which the
user can service or re-use in this or any other
product.

If you are in need of special assistance and the
information you require is outside the scope of this
manual, please contact your nearest service agent
orAustralian Monitor direct:

THE TECHNICAL OFFICER

AUSTRALIAN MONITOR

C/- AUDIO TELEX COMMUNICATIONS PTY LTD

PRIVATE BAG 149,

SILVERWATER. N.S.W. 1811

AUSTRALIA.

!WARNING!

DO NOT EXPOSE TO EITHER

RAIN OR MOISTURE

The amplifier should not be operated in a situation
where it may encounter the entry of water, rain, or
any fluids. To expose the unit to the above conditions
may make the operation of the unit hazardous and
increase the risk of electrical shock.

Phone Fax
Local [phone] (02) 9748-2537
International 61-2-9647-1411 61-2-9748-2537

Email [e-mail]
Internet www.australianmonitor.com.au

Rev 2 16/06/04
Rev 3 26/06/04
Rev 4 28/06/04
Rev B 28/06/04

Features:

>

Custom designed, 2RU heavy duty steel
chassis.

Open, modular construction for ease of

>

servicing.

Symmetrical layout - even weight distribution.

>

High current power supply.

>

High efficiency toroidal mains transformer.

>

Binding post and 4 pole speaker output

>

connection (no 4 pole speaker outputs on
SY400V, SY800V, SY4200 & SY6125).

Stereo or bridged operation (no bridging

>

available on SY400V & SY800V).

Input signal strapping (loop through) connectors

>

(not available on SY6125).

>

Balanced inputs and buffered attenuators.

1 Watt output indication (2.828 volts).

>

1 dB below output clip indication.

>

Efficient front to back cooling.

>

Dual, twin speed axial fans.

>

Multi-role output fault indication.

>

Front carry handles. Rear rack mount ears.

>

Signal ground lift switch.

>

Built in limiter circuit.

>

High-quality, close-tolerance components

>

throughout.

Protection Features

>

Suppression of inrush current at mains turn-on.

Input muting at turn-on.

>

Input overvoltage protection.

>

Radio-frequency interference suppression.

>

Short-circuit protection and indication.

>

High overload mains fuse.

>

Austr alian Monitor

>

Internal, independent DC supply rail fuses.

Layout, grounding, decoupling and componentry

>

have been optimized to provide the user with

, and .stability reliability longevity

Contents

Page

1. Introduction 5

2. Controls, Connectors and Indicators 6

2.1 Front Panel 7

2.2 Rear Panel 11

3. Installation 14

4. Operation 16

5. Maintenance 18

6. Specification 20

List of Illustrations

Page

Figure 1. Block Diagram 5

Figure 2. Front Panel Layout(SY6125, SY1200, SY4200) 6

Figure 3. Rear PanelLayout (SY400, SY1600) 9

Figure 4. Rear PanelLayout (SY6125, SY4200, SY400V) 10

Figure 5.Top Lid Layout (SY6125, SY4200) 13

Figure 6. Speaker Connector Wiring 15

1. Introduction

Introduction 5

Congratulations on choosing Australian Monitor for
your professional amplification requirements.

The design of our Synergy-Series Audio Power
Amplifiers embraces all the aspects of a well
designed amplifier. The visual design, mechanical,
electrical and sonic parameters, along with our
dedicated manufacturing process, have all been
optimized to provide a professional tool that exhibits
quality, reliability and longevity.

The Synergy-Series amplifiers are 2 unit (3.5") high,
19" wide, rack mountable units.

Each channel of the amplifier comprises a balanced
active input with a buffered attenuator driving a
differential class A drive stage which in turn drives a
fan-cooled, class AB, BJT output stage configuredas
an emitter follower. The amplifier operates from a
high current-capable linear power supply.

These amplifiers have been specifically designed to
deliver their high power output with minimal
distortion, and provide the critical degree of control
required by your speakers, at high duty cycles for
extended periods.

Austr alian Monitor

Figure 1 Amplifier Block Diagram

6 Controls & Connectors

2. Controls, Connectors & Indicators

MAX

LEVEL-D

MIN

D

STATUS

C

OVERLOAD

MAX

LEVEL-C

MIN

FAULT

POWER

THERMAL

SY 4200

MAX

LEVEL-B

MIN

B

STATUS

A

OVERLOAD

MAX

LEVEL-A

MIN

Australian Monitor

MAX

LEVEL-F

MIN

F

STATUS

E

OVERLOAD

MAX

LEVEL-E

MIN

MAX

LEVEL-D

MIN

D

STATUS

C

OVERLOAD

MAX

LEVEL-C

MIN

MAX

LEVEL-B

MIN

B

A

STATUS

OVERLOAD

MAX

LEVEL-A

MIN

POWER

FAULT

THERMAL

SY 6125

Figure 2 Front Panel Layout (left to right - SY4200, SY1200, SY6125)

Controls & Connectors 7

Front Panel

The Synergy Series differ only slightly across all
models and all share the same features on their front
panels.

Figure 1

amplifiers, SY4200, SY1200 & SY6125. The
SY1200 looks the same as the SY400, SY800,
SY1600, SY400V & SY800V. The functions of the
controls and indicators are as follows:

1 Attenuator

2 Status Indicator

shows the panel layout of three Synergy

Level control for your amplifier is provided by a
potentiometer on the front panel and indicates
gain. There are 2 controls on all models
except the SY4200 which has 4 controls and the
SY6125 which has 6 controls. Each control is
labelled for the channel which it controls.

This is a dual colour LED which displays the
status of the output stage and displays three
levels of operation.

These levels are:
Below 1 watt (unlit)
1 watt and above ( )
1dB below actual clipping ( )

The LED will turn green once the output voltage
exceeds 2.828 volts (1 watt re 8 ohms or 2 watts
re 4 ohms). For the SY400V & SY800V the output
voltage is 10 volts & 7.070 volts (2 watts re 50ohm
& 25ohm) respectively

The LED will change to red once the output
exceeds the -1dB point before actual clipping of
the amplifier’s output stage. The threshold of the ­1dB point is referred to the amplifier supply rails
and alters with changes in the mains supply,
changes in the load and duty cycle fluctuations.

The attack and decay time (ballistics), of the
status circuit are those of a Peak Programme
Metre (P.P.M.)

If using this indicator to line up sensitivities, apply
a steady state tone (e.g. slate on a mixing
console). The 1 watt level is the mid-point
between the indicator illuminating and
extinguishing green.

Synergy

green
red

NOTE: The amplifier is not damaged by running
into clipping, . To maximise
the life of your speakers, try to keep clipping
infrequent. Clipping on the SY400V & SY800V
may cause speaker transformers to saturate
causing the amplifier to shut down. For this
reason the voltage limiters should always be
engaged on the SY400V & SY800V (see Rear
Panel-Limiter Switch on page 11).

but speakers may be

3 Overload Indicator

This LED will illuminate when an overload

amber

condition exists.

Overload conditions can occur under extreme
operating conditions such as:

- complex or very low loads

- over driving the amplifier

- speaker transformer saturation

It should be noted that the minimum load for the
amplifier is 4 ohms per channel (8 ohm bridged)
except the SY400V which has a minimum load of
50 ohms per channel and the SY800V which has
a minimum load of 25 ohms per channel. (The
SY400V & SY800V cannot be bridged).

If an overload occurs, the amplifier will shut down
and mute all outputs except the SY6125 &
SY4200 which will only mute the channel with the
overload. If the overload is only transitory, then
the amplifier will resume normal operation after
approximately 7 secs. If the fault is continuous,
then the amplifier will remain muted.

4 Power Switch

Press the switch to for power ( )and
for power ( ). At start-up (turn-on), the input
to the amplifier is muted for approximately two
seconds.

off 0

up on I down

5 Thermal Indicator

In the advent of a thermal overload, this LED will

red,

turn indicating that the internal operating
temperature of one or both amplifier channels
has exceeded a safe level of operation and the
channels will be automatically muted. The fans
will continue to run and once the effected
channel/s have had a cool-down period, they will
un-mute and return to normal operation.

Austr alian Monitor

8 Controls & Connectors

NOTE: You should always ensure that the fan
grille is kept clean and free from the build up
of dust andlint

of your amplifier and reduce the possibility of it
prematurely going into thermal shutdown mode.
See the section “Installation - Cooling “ on page
14 for recommended cooling procedures.

. This will ensure longer operation

6 On Indicator

This LED will illuminate and indicates that
the amplifier is on and receiving mains power.

blue

7 Fault Indicator

This LED indicates a significant problem with

red

the amplifier and the amplifier should be returned
to an authorised technician for servicing.

Controls & Connectors 9

Figure 3 Rear Panel Layout (left to right - SY400, SY1600)

Austr alian Monitor

10 Controls & Connectors

A

CH A

WIRING

Pin2= +ve

Pin 1 = Gnd

Pin3=-ve

SIGNAL INPUT

CH-A

12

LIFT

GND

CH-B

SPEAKER OUTPUTS ( 125 W re 4 Ohms )

BRIDGE

PUSH TO

CH-C

2
1

LIFT

GND

BRIDGE

B

Serial No

CH A

(8 Ohms Min)

SY 6125

C

D

CH B

SPEAKER OUTPUTS

CH B

(200W/4 Ohms each)

BRIDGE

(8 Ohms Min)

Serial No

A

SY 4200

B

C

BALANCED INPUTS

BRIDGE

CH-D

(8 Ohms Min)

BRIDGE

PUSH TO

E

STEREO: 2x 200W/100V OUTPUT/CLASS 2

V

WIRING

Pin 1 = Gnd

SIGNAL INPUT

CH-E

SPEAKER OUTPUTS ( 125 W re 4 Ohms )

12

LIFT

GND

F

ENGINEERED BY AUDIO TELEX COMMUNICATIONS PTY LTDSYDNEY AUSTRALIA

CH-F

Pin2= +ve

Pin3=-ve

MAINS

A)

50/ 60 Hz (1350 V

(F3) FUSE 6.3Amps S.B.

230 V

BALANCED INPUTS

CH C

CH C

SPEAKER OUTPUTS

CH D

CH D

(200W/4 Ohms each)

BRIDGE

(8 Ohms Min)

D

ENGINEERED BY AUDIO TELEX COMMUNICATIONS PTY LTDSYDNEY AUSTRALIA

A)

MAINS

50/ 60 Hz (1333 V

(F3) FUSE 6.3Amps S.B.

230 V

Figure 4 Rear Panel Layout (left to right) - SY400V, SY6125, SY4200

Controls & Connectors 11

Rear Panel

8 Balanced Input

A female 3-pin XLR type connector is provided on
each input:
Pin 1 = Signal Ground;
Pin 2 = Hot (non-inverting or in phase);
Pin 3 = Cold (inverting or reverse phase).

8a Signal Strapping

A male 3-pin XLR type connector is provided (not
on SY6125) and wired in parallel with the female
input XLR for strapping / looping signal between
amplifiers.

9 Signal Ground Lift Switch

When this switch is engaged it disconnects signal
ground from the input connectors on both
channels. It is intended to be used when “hum” is
caused by earth loops (due to different ground
potentials between source equipment and the
amplifier) or stray magnetic field pick up on the
input ground/shield wiring. (It does not interrupt
signal ground continuity on the strapping
connector).

before engaging this switch!

The ground lift for the SY6125 is a DIP switch and
is located on the rear panel, one switch per
channel. It should be slid up to lift the ground.
ground lift for the SY4200 is a DIP switch and is
located inside the amplifier and accessed
through the lid, one switch per channel. It should
be slid to the rear to lift the ground.

10 Binding Post Outputs

Touch proof binding posts (banana jacks) are
provided for speaker output termination with
banana plugs or bare wire. The red post is used

positive

as and the black post is used as

negative

posts. (
bridged).

The amplifier should be turned off

. For bridge connection, use only the red

The SY400V & SY800V cannot be

The

A is considered the dominant channel and has
both channels wired to the speaker connector.
See the installation section of this manual for
detailed information on speaker connector
wiring.

11 Mains Connection

Your amplifier is fitted with either an
internationally recognised IEC mains inlet
connector (SY400, SY800, SY1200, SY400V,
SY800V, SY6125, SY4200) or has an internally
connected mains lead (SY1600).
Please ensure that the connecting mains lead for
use with the IEC connector is of an approved type
and is of sufficient current carryingability.

NOTE: Yourunit must always beearthed!

12 Mains Fuse or Circuit Breaker

Either a 20mm x 5mm fuse drawer is provided
within the housing of the IEC mains connector
(SY400, SY800, SY1200,
SY6125, SY4200
resettable circuit breaker (SY1600).

Fuse:
When you receive your amplifier it will have a
working fuse and a spare fuse inside the fuse
drawer. The drawer can only be opened once the
mains lead is removed from the connector. The
fuse is provided to protect both the mains and
your amplifier as well as reduce the degree of
damage if an internal fault exists.
When replacing the fuse, replace with an anti­surge (slow blow) type of the current rating
indicated on the back panel above the fuse
holder.
Warranty does not cover a blown fuse or any
resulting damage due to the use of an incorrect
fuse rating or type.

Breaker:
If the circuit breaker trips, allow 3 mins for the
contacts to reset thermally before pushing the
reset button to reset it mechanically.

) or the amplifier is fitted with a

SY400V, SY800V,

10a Speaker Output Connector

A 4 pole speaker connector is provided (not on
SY400V, SY800V, SY6125, SY4200) as an
additional speaker output. This standard of
loudspeaker-to-amplifier connection allows
access to both channels of the amplifier via the
one connector for bi-amp applications. Channel-

Austr alian Monitor

13 Bridge Switch

Pushing this switch engages the
BRIDGED/MONO mode of operation. In this
mode your amplifier will only accept signal
applied to channelA’s input XLRs and the level of
both channels will be controlled by channel A’s

in

12 Controls & Connectors

attenuator. The output from channel B will
automatically be of the opposite polarity
(reversed phase) andspeaker termination should
be sourced from the red binding-post outputs.
Alternatively, the speaker could be connected to
poles 1+ & 2+ of the 4 pole speaker connector
(see Installation - Output Wiring on page 11).

The SY400V & SY800V cannot be bridged.

The SY6125 allows bridging of channels B & C
and channels D & E. The bridge switch is located
on the rear panel. When channels B & C are
bridged, channel B input should be used and the
red binding post of channel B is positive while the
red binding post of channel C is negative. When
channels D & E are bridged, channel E input
should be used and the red binding post of
channel E is positive while the red binding post of
channel D is negative.

The SY4200 allows bridging of channels A & B
and channels C & D. This is done through the lid
with a switch. Sliding the switch toward the rear
enables bridging. When channels A & B are
bridged, channel A input should be used and the
red binding post of channelA is positive while the
red binding post of channel B is negative. When
channels C & D are bridged, channel C input
should be used and the red binding post of
channel C is positive while the red binding post of
channel D is negative.

14 Limiter Switch

Pushing this switch in engages the clip limiter
circuitry. On the SY6125 & SY4200 the limiter
switch is located inside the amplifier and is
accessed through the lid. Slide the DIP switch
up/towards rear of amplifier to engage the limiter.
The threshold level is referenced to the supply rail
and the output voltage is sampled allowing true
clip detection and limiting.

itself and shut down. This is worst at lower
frequencies. Engaging the limiter helps control
this problem.

15 Filter Switch

The SY4200 and SY6125 have low pass filters
included on-board the amplifier. The filters are
preset to 125Hz with 18dB/octave roll off.

On the SY4200 the filter is only on channel C but
will also affect the bridged configuration. This
arrangement is suitable for 2.1 systems with the
stereo left/right pair on channels A & B and the
sub on the bridged channels C & D. The channel
C input should be used. The filter is engaged by
sliding the switch located through the top lid to the
rear of the amplifier.

On the SY6125 there are two filters. One filter is
on channel B but will also affect the bridged
channels B & C. Channel B input should be used.
The other filter is on channel E but will also affect
the bridged channels D & E. Channel E input
should be used. Many configurations are
possible with this amplifier.An example would be
in a 5.1 system. Channels A & B running the left
and right, channel C running the centre speaker,
channel E bridged with channel D running the sub
and channel F running the rear surrounds. The
filters are engaged by sliding the DIP switch
located through the top lid to the rear of the
amplifier.

NOTE:

SY400V or SY800V amplifier

switch engaged.

The nature of transformers means that peaks in
program music could saturate the internal
transformer and/or the speaker transformers
attached to the amplifier. When a transformer
saturates, it no longer acts as a transformer but
rather as a thick piece of wire. This appears to
your amplifier as a short circuit so it will protect

It is important to always operate your

with the limiter

Controls & Connectors 13

15

GND
LIFT

DIP 1

()

1 1

2 2

CH A

CH B

CH C=LP

SW 1

DIP 3

BRIDGE

CH-A/B ( ) CH-C/D ( )

SW 2

FILTER
ON ( )

LIMITER ON ( )

11

22

CH A

CH B

DIP 4

CH D

CH C

GND
LIFT

()

BRIDGE

DIP 2

CH D

CH C

SW 3

FILTER

ON ( )

DIP 3

DIP 1

LIMITER

ON ( )

1 1112 222

CH-B

CH-A

CH-C

DIP 2

CH B

15

Figure 5 Top Lid Layout (top to bottom - SY4200, SY6125)

Austr alian Monitor

CH-E

LIMITER

ON ( )

CH-D

CH-E

DIP 4

CH-F

14 Installation

3. Installation

fans to evacuate the heated air and aid the flow of
cool air through the unit.

Power Requirements

Power consumption for your model of the Synergy
Series amplifier is indicated on the rear panel for
maximum output.

Ensure that mains voltage is the same as the
rear panel mains voltagemarker (+/- 10%).

your

Mounting

Your amplifier is designed for standard 19" rack
mounting and occupies 2 EIA rack units (3.5"). The
mounting centres are:

Vertical: 3.0"(76.2mm)

Horizontal: 18.2" (461.2mm) to 18.7" (473.8mm).

The slots in the mounting flange will accept bolt
diameters up to 1/4" (6.35mm).

We recommend that you provide additional support
for the amplifier, especially if road use is planned, as
the weight could bend some rack frames. This
support can be provided by secure shelving, support
rails or arear rack mounting strip to match upwith the
rear rack mount ears provided on your Synergy
Series amplifier.

Input Wiring

IMPORTANT
Do not directly connect pin 1 on the amplifier’s input
or strapping XLR, to the amplifier’s chassis, speaker
ground or power ground!

NOTE
Input signal ground is not to be used as a safety
ground (earth)

The input to your amplifier is a balanced 3-pin
configuration and requires all three pins to be
connected. Only high quality twin-core shielded
cable should be used.

When wiring for a balanced source, the connector
going to the input of your amplifier should bewired as
follows:

Pin 1 = GROUND / SHIELD.
Pin 2 = HOT (In Phase- non inverting).
Pin 3 = COLD (Reverse Phase - inverting).

When wiring from an unbalanced source you
ensure that pin 3 is connected to pin 1(input ground),
either by linking the pins in the input connector or by
the source equipment's output wiring.

When wiring for an unbalanced source:

.

must

Cooling

Each channel of your Synergy Series amplifier is
cooled by an axial fan which draws cool air from the
front of the amplifier and expels the heated air out
the rear of the amplifier. These amplifiers offer two
speed fans which run at half speed, switching to full
speed when the internal heatsink temperature
exceeds 60 C (128 F).

An unrestricted airflow into and out from the
amplifier must be provided

air flow will cause heat to build up within the unit and
possibly force the unit into its thermal shutdown
mode.

If the amplifiers are to be operated in an environment
where the airflow is restricted such as sealed racks,
the cooling should be supplemented by extra cooling

00

. Any restriction of the

Pin 1 = GROUND/SHIELD
Pin 2 = HOT (in phasewith the amplifier’s output),
Pin 3 = GROUND/SHIELD (joins to pin 1).

NOTE:

In-line XLR connectors often have a termination lug
that connects directly to the chassis of the connector.
Do link this lugto pin 1 at theamplifier’s input asit

not

will defeat the amplifier’s input grounding scheme.

Output Wiring

When wiring to your speakers always use the largest
gauge wire your connector will accept. The longer
the speaker lead, the greater the losses will be,
resulting in reduced power and less damping at the
load. We recommend using a heavy duty, two core
flex (four core flex if bi-amping) 10 to 12 gauge (2mm
to 2.5mm or 50/0.25 or equivalent) as a minimum.

2

2

Binding Post Outputs

When terminating to the 4 mm binding post (banana
jack) output connectors, banana plugs or bare wires
can be used. The red terminal is and the
black terminal is (ground).

negative

positive

Installation 15

connecting to the outputs separately or together.
Connecting through a single connector has the
advantage of minimising connections, preserving
phasing and simplify channel allocation, which is
particularly important when or in
mode.

bi-amping bridge

If running in BRIDGE mode, only the binding
posts are used.

For the SY400, SY800, SY1200, SY1600:
When bridging, Channel A provides the positive
output to the load and channel B provides the
negative output to the load.

For the SY6125:
When bridging B & C,
positive output and channel C provides the negative
output to the load.

hen bridging D & E, channel E provides the

W
positive output and channel D provides the negative
output to the load.

For the SY4200:
When bridging A & B, channelAprovides the positive
output and channel B provides the negative output to
the load.
When bridging C & D, channel C provides the
positive output and channel D provides the negative
output to the load.

channel B provides the

red

IMPORTANT

Do not overload your amplifier by connecting the
channel B output twice!

Channel A is used as the “dominant” channel and
when sourcing a dual output from Channel A, the
following standard should normally be used
(depending on speaker system wiring):

ChannelA= Left or Low Frequencies.

Channel B = Right or High Frequencies.

When in mode:

Pin 1+ = Bridge Output Positive
Pin 2+ = Bridge Output Negative.

bridge

There exists no means of bridging your SY400V
or SY800V amplifier.

Speaker Outputs

(NOTE: There are no 4 pole speaker connectors on
the SY400V,SY800V, SY6125 or SY4200).
When using the 4 pole speaker connector for
speaker output, use only the mating 4 pole in-line
connector. This connector is designed so that both
channels can be fed from a single connector.

Two speaker connectors are provided on the
amplifier.

The "Channel A" speaker connector actually carries
both channel A & channel B outputs (see :
Speaker Connector Wiring Diagrams).

The "Channel B" speaker connector carries the
Channel B output only.

This arrangement allows you the option of

Figure 6

Figure 6. Speaker Connector
Wiring Diagram

Austr alian Monitor

16 Operation

4. Operation

IMPORTANT
All signal source equipment should be
adequately earthed. This not only
ensures safety but everybody

else's as well. Faults can and do occur in
mains connected equipment where the chassis can
become “live” if it is not properly earthed. In these
instances, the fault in a “floating” (ungrounded) piece
of equipment will look for the shortest path to ground,
which could possibly be your amplifier's input. If the
fault current is large enough, it will destroy the input
to your amplifier and look for the next available path,

may be you

which !

Before making any connections

Series amplifier, observe the following:

Ensure the mains voltage supply matches the
label on the rear panel of your amplifier (+/- 10%).
Ensure that the power switch is OFF.
Ensure that all system grounds (earth) are
connected from a common point. Avoid powering
equipment within a system from multiple power
sources that may be separated by large
distances.
Check the continuity of all interconnecting leads
to your amplifier; ensure that there are no open or
short circuited conductors.
Ensure that the power handling of your load
(speakers) can adequately cope with the power
output of the amplifier.

your

to your Synergy

amplifier goes through an initialising period before it
will accept signal. The Inrush Current Suppression
(ICS) circuit is in operation for the first 0.5 seconds.
This limits the mains current, to prevent "nuisance­tripping" of circuit breakers.

During this period you will hear a couple of relays
“click”, indicating mains is now directly applied to the
amplifier and the signal path is connected.

While the ICS circuit operates there is also a 30dB
mute on the signal input. After two seconds this mute
will release, allowing any applied signal to pass un­attenuated.

When switching the amplifier off, a couple of
seconds before switching the amplifier on again.
This allows the ICS circuit to reset.

wait

Level Matching

The normal operating position for the attenuator is
the max position (fully clockwise, no attenuation). In
this position the amplifier operates at full gain.
Turning the attenuator back (anticlockwise) reduces
the input sensitivity.

NOTE:
If full power output is required, you should operate
your amplifier with the front panel attenuator above
the half way (12o’clock) position, otherwise clipping
of the input circuitry and its resultant distortion will
occur before full output power is achieved.

Before operating

ensure that:

- The attenuators are at the “OFF” position (fully
anticlockwise).

- The GROUND LIFT Switch is not engaged
(should be in the “out” position).

- The BRIDGE Switch is not engaged if you are not
running the amp in bridged mode.

your Synergy Series amplifier,

Powering Up

REMEMBER
The amplifier should be the piece of equipment
that you turn and the piece of equipment that
you turn .

We recommend turning the attenuators on your
amplifier when turning the unit on.
When you power up your Synergy Series, your

on first

off

down

last

Sensitivity

Your amplifier is a linear device operating with a fixed
input to output voltage gain (less attenuation). The
maximum output voltage swing is determined by the
applied mains voltage, load, load type and the duty
cycle of the applied signal.

input sensitivity

The for your Synergy Series
amplifier when the attenuator is at maximum position
(fully clockwise) is nominally:

+2.2dBu (1.0 voltsin) for ratedpower into a4 ohm
load.

Each channel of your Synergy Series amplifier has a
nominal balanced of 20kOhms
(@1kHz) and should not present a difficult load for
any signal source.
Your signal source (i.e. the equipment feeding signal
to the amplifier) should have an

input impedance

output impedance

Operation 17

of 600 Ohms or lower to avoid unwanted high
frequency loss in the cabling.

Input overload occurs at +20.5dBu (8.25 volts).

Hum Problems

Most equipment is designed for minimum hum when
used under ideal conditions. When connected to
other equipment, and to a safety earth in an
electrically noisy environment, problems may occur.

The three "E"s of hum and hum related noise which
can plague your audio system are:

a) Electrostatic radiation,
b) Electromagnetic radiation, and
c) Earth loops

Electrostatic

system elements, causing an interference voltage
that mainly affects higher impedance paths, such as
amplifier inputs. The source is generally a nearby
high voltage, such as a mains lead or a speaker lead.
The problem can usually be reduced by moving the
offending lead away, or by providing additional
electrostatic shielding (i.e. an earthed conductor
which forms a barrier to the field).

Electromagnetic

currents into system elements that mainly effect
lower impedance paths. Radio transmitters or stray
magnetic fields from mains transformers are often
the cause of this problem. It is generally more difficult
to eliminate this kind of interference, but again,
moving the source away or providing a magnetic
shield (i.e. a steel shield) should help.

Earth loops

various pieces of equipment and their connections to
various safety earths.

radiation capacitively couples to

radiation induces interference

can arise from the interfacing of the

Ensure the mains power for the audio system is
“quiet” i.e. without equipment on it such as air­conditioning, refrigeration or lighting which may
generate noise in the earth circuit.

Ensure all equipment within the system shares a
common ground/ safety earth point. This will
reduce the possibility of circulating earth
currents, as the equipment will be referenced to
the same ground potential.

Ensure that balanced signal leads connecting to
the amplifier are connected to earth at one end
only.

Signal Ground-Lift Switch

When proper system hook-up has been made, you
may still have some hum or hum related noise. This
may be due to any of the previously mentioned
gremlins.

Your Synergy Series amplifier has a “Signal Ground
Lift” switch which disconnects the input ground
wiring from the amplifier. A substantial drop in hum
and/or hum related noise can result from the
judicious use of this switch.

NOTE
If the input ground lift switch is used, you must
ensure adequate shielding of the input wiring. If the
signal source equipment does not provide adequate
shielding (i.e. a definitive connection to ground), you
must disconnect the shield from the input
connector's ground pin (Pin-1) and re-connect it to
the "drain" contact on the input connector. This will
ensure the shield on your input wiring actually goes
to the amplifier chassis and subsequently to earth.

DO NOT CONNECT PIN-1 DIRECTLY TO THE

DRAIN CONNECTION.

This is by far the most common cause of hum, and it
occurs when source equipment and the amplifier are
plugged into different points along the safety earth
where the safety earth wiring has a current flowing
through it. The current flowing through the wire
produces a voltage drop due to the wire’s resistance.
This voltage difference between the amp earth and
source equipment earth appears to the amplifier's
input as a signal and is amplified as hum.

There are three things you can do to avoid earth loop
problems:

Austr alian Monitor

You will defeat the amplifiers internal grounding
scheme and possibly cause instability to the
amplifier.
Always ensure that your amplifier is and the
attenuators are when you engage this switch.
This switch should only be used when the amplifier is
operated from a signal source.
NOTE: Be wary of outputs, these
are often no more than floating outputs.

down

balanced

quasi-balanced

unbalanced

off

18 Maintenance

5. Maintenance

Only or persons

competent qualified

should attempt any service or

maintenance of your amplifier.

Your Synergy Series amplifier will need minimal
maintenance. No internal adjustments need to be
made to the unit to maintain optimum performance.

To provide years of unhindered operation we
suggest a maintenance inspection be carried out on
a regular basis, say every 12 months or so.

Fans

Due to the openness of the air path through your
Synergy Series amplifier, very little dust should settle
within the amplifier. The unit has been designed so
that any dust and/or foreign particles that do settle
within the amplifier will not unduly hinder the cooling
of the amplifier.

The grille in front of the fans will act to limit the
amount of dust and lint entering the amplifier. You will
find in time that there will be a build up of dust and lint
on the grille which may start to hinder the airflow
through the amplifier. You should periodically
remove the dust and keep the grille clean. Removal
of dust from the rear grille will also aid cooling.

Over time, dust may build up on the leading edge of
the fan blades and reduce their cooling efficiency.
The time taken for this to happen will depend on the
environment and the amount of use.

The fan blades are accessible once the lids
are removed and can be easily cleaned. You

need only hold the fan rotor still and wipe the
dust off the blades. Many users the fan and use
compressed air to blow the dust off the fan blades. It
is important to note that the fan blades must be held
still whilst blowing air over the blades otherwise you
may burn out the bearings in the fan.

stall

Fuses

Along with rear panel mains fuse, there are four (4)
rail fuses provided internally in the unit. These rail
fuses are in series with the positive and negative
output supply to each amplifier channel and provide
overall protection for the output stage. If the amplifier
is subjected to heavy use such as short circuits, 2
ohm or bridged 4 ohm loads, these fuses will
eventually fatigue and may require replacing to
ensure they do not fail at an inconvenient time.

NOTE
Make sure the unit is and is
unplugged from the mains. Give the
main filter capacitors time to discharge
before removing lids and inspecting the
fuses.

You should replace the fuse if the element is

sagging or discoloured

same type fuse and current rating.

When checking for a failed fuse, do not rely on visual
inspection alone. You should use an ohm meter to
check continuity.

. Only ever replace with the

off

19

Austr alian Monitor

20 Specifications

Model:

SY 400

Output Power

Per Channel

Single channel driven
Both channels driven 200W
(2 ohm loads not recommended)

Bridge mode
8 ohm load 400W
(4 ohm bridging not recommended)

Voltage Gain

Output Impedance

Damping factor

Slew rate

@ 4 ohms 0.1% THD

240W

28.3

@ 1kHz <0.021ohms

(@ 1kH re 8 ohms) > 375:1

>40 V/µs

Model:

SY 800

Output Power

Per Channel

Single channel driven 430
Both channels driven 375W
(2 ohm loads not recommended)

Bridge mode
8 ohm load 750W
(4 ohm bridging not recommended)

Voltage Gain

Output Impedance

Damping factor

Slew rate

@ 4 ohms 0.1% THD

W

38.7

@ 1kHz <0.019ohms

(@ 1kH re 8 ohms) > 430:1

>40 V/µs

Frequency response

@ 1KHz

Rated Power into 4 ohm (-3dB)

15 Hz- 80 kHz

Dimensions

H,W,D= (87 x 482x400)mm
Shipping Weight = 12 Kg

Input Power

575 VA

Common Specifications

(To all SY Amplifiers)

Distortion

THD (@ 1kHz) <0.02%
IMD SMPTE (60Hz : 7kHz 4:1) <0.03%

Input Impedance

Input Sensitivity

Input CMRR

(re 4ohm, 1dB below clip

)

20kohms

1Vrms

>80dB

Frequency response

@ 1KHz

Rated Power into 4 ohm (-3dB)

15 Hz- 70 kHz

Dimensions

H,W,D= (87 x 482x400)mm
Shipping Weight = 15 Kg

Input Power

1065 VA

Signal/Noise Ratio

Linear >97dB
A-Weighted >104dB

Crosstalk

>70dB

Indicators

Power, Status/Clip (L/R), Overload, Thermal, Fault

Specifications 21

Model:

SY 1200

Output Power

Per Channel

Single channel driven 710
Both channels driven 600W
(2 ohm loads not recommended)

Bridge mode
8 ohm load 1200W
(4 ohm bridging not recommended)

Voltage Gain

Output Impedance

Damping factor

Slew rate

@ 4 ohms 0.1% THD

W

49.0

@ 1kHz <0.018ohms

(@ 1kH re 8 ohms) > 450:1

>41 V/µs

Model:

SY 1600

Output Power

Per Channel

Single channel driven 920
Both channels driven 800W
(2 ohm loads not recommended)

Bridge mode
8 ohm load 1600W
(4 ohm bridging not recommended)

Voltage Gain

Output Impedance

Damping factor

Slew rate

@ 4 ohms 0.1% THD

@ 1kHz <0.019ohms

(@ 1kH re 8 ) > 430:1

W

56.5

ohms

>41 V/µs

Frequency response

@ 1KHz

Rated Power into 4 ohms (-3dB)

Dimensions

H,W,D= (87 x 482x450)mm
Shipping Weight = 17 Kg

Input Power

Forced air cooled

]

Equipped with XLR male/female

]

inputs

]

Dual output connectors, binding
posts and 4 pole speaker
connectors

15 Hz- 75 kHz

Frequency response

@ 1KHz

Rated Power into 4 ohms (-3dB)

Dimensions

H,W,D= (87 x 482x450)mm
Shipping Weight = 20 Kg

1650 VA

Input Power

Features of the SY Series

]

Toroidal mains transformer

]

CE Approved (EMC & LVD)

15 Hz- 62 kHz

2100 VA

]

GND lift facility

]

Clip limiter circuit provided standard

Austr alian Monitor

22 Specifications

Model:

SY 6125

Output Power

Per Channel

Single channel driven 130
All channels driven 6 x 125W
(2 ohm loads not recommended)

Bridge mode
8 ohm load 2 x 250W
(4 ohm bridging not recommended)

Voltage Gain

Output Impedance

Damping factor

Slew rate

@ 4 ohms 0.1% THD

W

22.3

@ 1kHz <0.030 ohms

(@ 1kH re 8 ohms) > 250:1

>40 V/µs

Model:

SY 4200

Output Power

Per Channel

Single channel driven 210
All channels driven 4 x 200W

Bridge mode
8 ohm load 2 x 400W
4 ohm load 2 x 600W

Voltage Gain

Output Impedance

Damping factor

Slew rate

@ 4 ohms 0.1% THD

@ 1kHz <0.020 ohms

(@ 1kH re 8 ) > 400:1

W

28.3

ohms

>40 V/µs

Frequency response

@ 1KHz

Rated Power into 4 ohms (-3dB)

Dimensions

H,W,D= (87 x 482x450)mm
Shipping Weight = 17 Kg

15 Hz- 80 kHz

Frequency response

@ 1KHz

Rated Power into 4 ohms (-3dB)

Dimensions

H,W,D= (87 x 482x400)mm
Shipping Weight = 14 Kg

15 Hz- 60 kHz

Specifications 23

Model:

SY 400V

Output Power

Per Channel

Single channel driven
Both channels driven 200W

Bridge mode

Voltage Gain

Frequency response

@ 1KHz

Rated Power into 50 ohm (-3dB)

@ 50 ohms 0.1% THD

240W

Not available

100

50 Hz- 30 kHz

Dimensions

H,W,D= (87 x 482x400)mm
Shipping Weight = 18 Kg

Model:

SY 800V

Output Power

Per Channel

Single channel driven 430
Both channels driven 375W

Bridge mode

Voltage Gain

Frequency response

@ 1KHz

Rated Power into 25 ohm (-3dB)

@ 25 ohms 0.1% THD

W

Not available

100

50 Hz- 30 kHz

Dimensions

H,W,D= (87 x 482x400)mm
Shipping Weight = 22 Kg

Austr alian Monitor

Australian Monitor

www.australianmonitor.com.au

Distributed by:

Audio Telex Communications Pty Ltd

ACN 001345482

www.audiotelex.com.au

International Enquiries

Ph: 612 9647 1411, Fax: [phone], E-mail: [e-mail]

Sydney

Ph: [phone], Fax: [phone], E-mail: [e-mail]

Melbourne

Ph: [phone], Fax: [phone], E-mail: [e-mail]

Brisbane

Ph: [phone], Fax: [phone], E-mail: [e-mail]

Adelaide

Ph: [phone], Fax: [phone], E-mail: [e-mail]

Perth

Ph: [phone], Fax: [phone], E-mail: [e-mail]

Auckland

Ph: [phone], Fax: [phone], E-mail: [e-mail]