AUSTRALIAN MONITOR PA800 Operation Manual

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AUSTRALIAN MONITOR PA800 Operation Manual | Manualzz

Australian Monitor f,4aoo

& fi4rzoo

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Operation Manual

(-

(_

IMPORTANT!

Please

read

carefully.

This operation manual contains important information regarding safety precautions, installation, performance, operation and maintenan

e

of your Piseries porcramplifier.

You should familiarize yourself with the contents of this manual before operating your amplifier.

Safety Precautions and Labelling

The rear panelof the unit has a numberof markings and intemationally recognized symbols related to the hazards and precautions that should be taken when operating MAINS connecled equipment.

REFER SERVICING TO

QUALIFIED PERSONNEL.

NO USER SERVICEABLE

PARTS

INSIDE.

The presence

of a

LIGHTNING FLASH

with

an arrowhead contained within

the

boundaries

of

a equilateral triangle is intended to alert the user that dangerous uninsulated voltages may exist within the units enclosure, These voltages may be of a sufficient magnitude as to constitute the risk of an electricalshock.

The user should not attempt to service the unit. Only qualified and knowledgeable personnel familiar with the internal workings of the unit should attempt any repair, servicing or authorized modification to the unit. The unit does not contain any parts which the usercan service orre-use in this oranyotherproduct.

This symbol is reinforced with the text:

RISK

ICAUT|ON! A

OF ELECTRICAL SHOCK

DO NOT

/A \

OPEN I \

lf

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 or

Australian Monitordirect:

The presence

of

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

IWARNING! /\

DO NOT EXPOSE

RAIN OR

TO EITHER

,/

I

\

MOISTURE ! \

THE TECHN ICAL I\4ANAGER

AUDIO TELEX COMMUN ICATIONS PTY LTD,

PRIVATE BAG 149,

SILVERWATER. N.S.W. 2128

AUSTRALIA.

Phone

Fax

Local

(02)96471411

(02)96,483698

lntemational

(612)%47 1411 (612) 9648 3698

Email

[email protected]

The unit should not be operated in a situation where it mayencounterthe entry ofwater, rain, oranyfl uids.

To expose the unit to the above conditions may make the operation of the unit hazardous and increase risk of electrical shock.

the ltu

Contents

1.

lntroduction

2.

Controls, Connectors and lndicators

2.1 Front Panel

2.2 Rear

Panel

3.

lnstallation

4.

Operation

5.

Bridge Mode

6.

Two Ohm or

Not

Two Ohm

7.

Maintenance

8.

Warranty

9.

Specification

Page

11

I

7

5

6

13

15

16

17

18

19

List of

Illustrations

Figure 1. Block Diagram

Figure 2. Front Panel Layout

Figure 3. Rear Panel Layout

Figure 4. Case Dimensions

Figure 5. "Speakon" Connector Wiring

Figure 6. Bridge Mode Speaker Wiring

Page

8

10

12

15

5

6

Features:

- Custom designed, 2RU heavy duty alloy

chassis.

- 1 Watt output indication (2.828volts).

- Open modular construction for ease of

servicing.

-

1 dB below output clip indication.

- Symmetrical layout - even weight

distribution.

- Massive heat-sink / heat-exchangers.

- well-regulating, high current power

supply.

- Efficient front to back cooling.

- High efficiency toroidal mains

transformer

Dual, twin speed axialfans.

- Binding post and Neutrik "speakon"

output

- Multi-role output fault indication.

conneCtion.

- Front carry handles. Rear rack mount ears.

- Stereo or bridged / mono

operation.

plug in signal modifiers (optional).

- lnput signalstrapping (loop through)

connectors.

- signal ground lifi switch.

- 21 Position detented

attenuators.

- Balanced inputs and buffered

- Highquality, close-tolerance components

attenuators.

throughout.

Protection Features

- Suppression of inrush current at mains

tum-on.

- High overload mains fuse.

- lnput muting at

tum-on.

- lnput overvoltage

protection.

- lnternal, independent DC supply railfuses.

- Layout, grounding, decoupling and componentry

- Radio-frequency interference

suppibssion.

have been optimized to provide the user with

- Short-circuit protection and

indication.

stability, reliability and longevity.

Ausfualhn Monitor

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Introduction

5

1. Introduction

Congratulations on choosing Australian your professional amplification

Monitor requirements.

for

The design of your

P4-Series e.mbrgce

Audio powerAmptifi all the aspects of a well designed unit. visual design, mechanical, electricalLnd sonic ers

The pa_ rameters, along with our dedicated process, have all been manufacturing optimized to provide a professional tool that exhibits quatity, reliability and longev_ itv.

The PA-Senes amptifiers are wide rack mountable units,

2

unit (3.5,,) tail,

19,,

Each cfrannel of the amplifier comprises a balanced active input with a differential class A drive stage which in turn

fan-cooled, a

buffered attenuator driving

class AB,

drivel a

MbSFET output

stage configured as a source follower. The unit operates from a high cunent-capable linear power supply.

These units have been specifically designed to de_ liver and provide the critical degree of your their high power output speakers,

at

with high duty minima'idistortion, control required by cycles

for

extended periods.

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Figure

1

Amplifier Block Diagram

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6

Controls &-

Connectors

2

.

Controls,

Connectors

&

Indicators

Figure

2

Front Panel Layout

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Controls & Connectors

7

Front

Panel

The

Pi

Series models have identical front panel layouts.

Fig u re

7 shows the panel layout of the PlSeries. The fu ndions of the controls and indicators are as fol lows:

3 Fault Indicator

This amber LED will flash when a fault condition exists.

I

2

Aftenuator

Level control for your amplifier is provided by a 21 position detented potentiometer and indicates gain reduction in decibels from the 0 dB position

(maximum gain, no attenuation).

Status Indicator

The fault detection circuit monitors the difference between drive and output in your amplifier.

lf you have a short on the speaker output (or a blown negative rail fuse) the LED will flash brightly in sync with the programme. This

LED will also flash with programme peaks for gross overloads or if the load is 2 ohms or less.

The circuit has two stages of operation:

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

These levels are:

Below 1

watt

1 watt and

(unlit)

above

(green)

1dB below actual

clipping

(red)

The LED will turn green once the output voltage exceeds 2.828 volts (1 watt re 8 ohms or 2 watts re 4 ohms). This is equivalent to:

24dB below rated powerfor a PA800 or

26dB below rated power for a PA1200.

The

LED

will

change

to

red once

the

output exceeds the -1dB point before actual clipping of the amplifiefs output stage. The threshold of the

-1dB point is refened 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), status circuit are those of

of

the

a

Peak Programme

Meter

(P.P.M.)

:.

lf using this indicator to line up sensitivities, apply a steady state tone (e.9. slate on a mixing console).

The 1 watt level

is

the mid-point between the indicator illuminating and extinguishing green.

1. lt will provide indication (e.9. gross overload) but does not affect the input signal (a faint flash).

2. lt will indicate and mute the input signal (e.g

shorted output) (brightly flashing or permanently on).

+

Power

Switch

5

Press the switch to the to the left for power off right for power on ( I

( 0

).

At

)and start-up (turn-on) the input to the amplifier is muted by 30dB for approximately two seconds.

On/Thermal Indicator

This is a dual colored LED which will normally be green and indicates that the amplifier is on and receiving mains power.

ln the advent of a thermal overload this LED will

tum red

indicating that

the

intemal operating temperature of one or both exceeded amplifierchannels has

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 cooldown period, theywill un-mute and return to normaloperation.

NOTE: The amplifier is not damaged by running into clipping, but speakers may be. To maximise

the

life of your speakers, try

to

keep clipping infrequent.

NOTE: You should always ensure that the fan grille is kept clean and free from the build up of dust and lint. This will ensure longer operation of your amplifier and reduce

the

possibility

of

prematurely going into thermal shutdown mode.

it

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Controls

81-

Connectors

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Figure

3

Rear

Panel Layout

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Controls &- Connectors

9

Rear Panel

to 24O volt mains supply.

5

Balanced Input

A female 3-pin XL type connector is provided on each input:

Pin 1 = SignalGround;

Pin 2

= Hot

(non-inverting or in phase);

Pin 3

= Cold

(inverting or reverse phase).

6a Signal Strapping

A male 3-pin XL type connector is provided and wired in parallel with the female input XLR for strapping / looping signal between amplifiers.

7

Signal Ground

Lift

Switch

When this switcfr is engaged it disconnects signal ground nels. from the input connectors on both chan-

lt 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. (lt does not intenupt signal ground continuity on the strapping connector). The amplifier engaging should be tumed off before

this

switchl

8

Binding Post Outputs

Touch proof binding posts (banana jacks) are provided

for

speaker output termination with banana plugs orbarewire. The red post is used as positive and the black post is used as negative.

8a SPEAKON

Ouput

Connector

The NEUTRIK (NL4MP) 4way SpEAKON connector is provided as an additional speaker output.

This emerging standard of loudspeakerto amplifi er connection allows a@ess to both channels of the amplifier via the one connec{or for bi-amp applications. Channel-A channel is considered the dominant and has both channelS wired

to

the

Speakon connector. See the installation section of this manual for detailed information on Speakon wiring.

9

Mains Connection

Your amplifier

is

fitted with

an

internationally recognised IEC mains inlet connector.

Please ensure that the connecting mains lead for usewiththis conneclor isof an approvedtype and is of sufficient current carrying ability.

Your Ptlauand P4tzm require a minimum mains lead rating of

1

0 amps when operate dfrom a22O

NOTE: Your unit must always be earthedt

10 Mains

Fuse

A 20mm x Smm fuse drawer is provided within the housing of the IEC mains connector. When you recieve 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 reducing 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 panelabovethefuse holder.

Warranty does not cover

a

blown fuse or any resulting damage due to an incorrect fuse rating or type.

The PAau requires

a 8

Amp Anti-Surge fuse.

The P4tzu requires a 10 Amp Anti-Surge fuse.

1l

Bridge Switch

Pushing this switch

MONO mode

in

engages the BRTDGED/

of

operation.

ln

this mode your amplifierwill only accept signal applied to channel

A's input XLRs and the level of both channels will

be

controlled

by

channel

A's

attenuator. The output from channel

B will automatically be of the opposite polarity (reversed phase) and speaker termination should

be

sourced from

the

red binding-post outputs.

D.C. Rail

Fuses (Internally fitted)

Removing the bottom lid will show PCB mounted fuse holders holding the rail fuse for each supply

to

each channel. These 3AG

.fast blou/' type fuses are in series with the positive and negative supply rails for each channel of your amplifier,s output stage. Thesefuses provide overall protection of the output stage and can also be used to isolate individual channels in case a fault condition exists.

lf you need to replace the rail fuses they must be replaced with the same type and cunent rating:

Prfu =

8 Amp.

Plrm

=

10 Amp.

NOTE: Replacement of the fuses should only be carried

out by a

competent and experienced person.

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Installation

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Dimensions

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lnstallation

1

I

3.

Installation

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

Power

Requirements

Model:

Mains Voltage

240,220-230

PlsM

Fuse Rating

8 Amps

lf

the units are to be operated in an environment wherethe airflow is restricted such as sealed racks or even when running 2 ohm loads, the cooling should be supplemented by extra cooling fans to evacuate the heated air and aid the flow of cool air through the unit.

Power

Power consumption at

idle =

120Watts.

consumption at rated

power

= 1450 Watts.

Input Wiring

IMPORTANT

Model:

Mains Voltage

240,220-230

P4rzu

Do not directly connecl pin 1 on the amplifieds input or strapping XLR, to the amplifier's chassis, speaker ground or power ground!

Fuse Rating

10 Amps

Power

Power

NOTE consumption at

idle = 160Watts.

lnput signal ground is not to be used as a safety consumption at rated

power = 22AOWatts.

ground (earth).

Ensure that your mains voltage is the same as rear panel mains voltage marker

(+l- the

lh91nu!toyouramplifierisa balanced3-pinsystem

1}o/o).

andrequiresallthreepinstobeconnected. Onlyhigh quality twin-core shielded cable should be used.

Mounting

Your amplifier

is

designed

for

standard 1g" rack mounting and occupies 2 EIA rack units (3.5"). The mounting centers are:

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

Vertical:

3.0" (76.2mm)

Horizontal: 18.2" (461.2mm)

to

18.7" (473.8mm).

Pin2

= HOT (ln Phase - non inverting).

Pin 3

= COLD

(Reverse Phase - inverting).

Pinl

=GROUND/SHIELD.

The slots in the mounting flange

will

accept bolt diameters up to 1/4" (6.35mm).

\A/hen wiring from an unbalanced source you must ensure that pin 3 is connected to pin

1

(input ground), either by linking the pins in the input connecloror by the source equipment's output wiring.

We recommend that you provide additionalsupport forthe amplifier, especially if road use is planned, as the weight can bend some racks otherwise. This support can be provided by secure shelving, support rails or a rear rack mounting strip to match up with rear rack mount ears provided on your the

Pl

Series amplifier.

When wiring for an unbalanced source:

Pin2

=

Hot (in phase with the amplifier's output),

Pin 3 = GrouncUShield (ioins to pin 1).

Pin 1 = Ground/Shield t

Cooling

Each chann el

d

your

PAm/Pltmamplifier

is cooled by an axial fan which draws cool air from the front of the unit and expels the heated air from the rear of the unit. These units offer two speed fans which run at half speed, switching to full speed when the intemal heatsink temperature exceeds 600C (1280 F).

An unrestricted airflow into and outfrom the unit must be provided. Any restriction of the airflowwill c€luse

NOTE: ln-line XLR connectors often have a termination lug thatconnects directlyto thechassis of the connector.

Do not link this lug to pin

1 at the amplifier's input as it will defeat the amplifier's input grounding scheme.

This lug is often referred to as a "drain" and is used to provide a termination to the chassis for shielding purposes when a floating signal ground is required between

the

source

and

destination,

or

when disconnecting the signal ground is required to reduee earth loop noise, ornoise induced intosignalgrounds from stray magnetic fields.

Aus;bdlan Monitor

I

2

Installotion

Output Wiring

When wiring to your speakers always use the largest gaugewire yourconnectorwill accept. The longerthe speaker lead the greater the losses will be, resulting in reduced power and less damping at the load. We recommend core flex using a heavy duty two core flex (four

if

bi-amping) 10

to

12 gauge (2mm2 to

2.5mm2 or 50/0.25 or equivalent) as a minimum.

The "Channel A" SPEAKON actually carries both channelA

& channel B outputs (se e Figure 5: Speakon

Connector Wiring Diagrams).

The "Channel B" SPEAKON canies the Channel B output only.

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 positive and the black terminal is negative (ground).

lf running in BRIDGE mode, only the red binding posts are used. Channel

A

provides the positive outputtothe load and channelB providesthe negative output to the load.

This anangement allows you the option of connecting to the outputs separately ortogether. Connecting through

a

single connector has the advantage of minimising connections, preserving phasing and simplified channel allocation, which is particularly important when bi-amping or in bridge mode.

IMPORTANT

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

Channel A is used as the "dominanf channel and when sourcing

a

dual output from Channel A the following standard should be used:

SPEAKON Outputs

When using the NEUTRIK SPEAKON (NL4MP) nector con-

for

speaker output, use only

the

mating

NEUTRIK NL4FC in-line connector. This connector is designed so that both channels can be fed from a single connector.

Two SPEAKON connectors amplifier.

are

provided

on

the

Channel A = Left or Low Frequencies.

Channel B = Right or High Frequencies.

\A/hen in bridge mode:

Pin 1+

= Bridge Output Positive

Pin 2+ = Bridge Output Negative.

SINGLE CONNECTION

CH

A/LEFI

OR

CH B/RIGHl

BRIDGED CONNECTION

DUAL CONNECTION BI.AMP CONNECTION

CHA

SPEAKON

Figure 5. "Speakon" Cannector Wring Diagram

ltu

Operation

l3

+.

Operation

IMPORTANT

All signal source equipment should be adequately earthed. This not only ensures your 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. ln these instances the fault in a "floating' (ungrounded) piece of equipment will look for the shortest path to ground which could possibly be your amplifie/s input. lf the fault cunent is large enough it will destroy the input to your amplifier and look for the next available path, which may be you!

Before making any connections

to

your

Piau/

Ptihzu amplifi er observe the fol lowing:

1.

Ensure the mains voltage supply matches the label on the rear panel of youramplifier (+/-

1

0%).

2.

Ensure that the power switch is OFF (to the left -

0)

3.

Ensure

that all

system grounds (earth). are connectedfrom a common point. Avoid powering equipment within a system from multiple power sources that may be separated by largedistances.

4.

Check the continuity of all interconnecting leads to your amplifier, ensure that there are no open or short circuited conductors.

5.

Ensure that

the

power handling

of

your load

(speakers) can adequately cope with the power output of the amplifier.

Before operat ngyour Pfuf?r'hzuamplifi er, ensure that:

-

The attenuators are at

the'OFF'

position (fully anticlockwise).

-

The GROUND LIFT Switch is not engaged (should be in

the'ouf

position).

-

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

t

Powering Up

REMEMBER

The amplifier should be the last piece of equipment thatyou tum on and thefirst piece of equipmentthat you tum off.

accept signal. The lnrush Cunent Supression (lCS) circuit is in operation for the first 0.5 seconds. This l imits the mains cunent to prevent "nuisance-tripping" of circuit breakers.

During this period the THERMAUON LED willflash red whilstthe mains voltage gradually charges up the power supply. You

will

then hear

a

relay "clicK, indicating mains is now directly applied to the amplifi er and the THERMAUON LED willbe green.

While the ICS circuit operates there is also a 30dB mute on the signal input. Aftertwo seconds this mute

will

release, allowing any applied signal

to

pass unattenuated.

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

Level

Matching

The normal operating position for the attenuator is the "0 dB" position (fully cloclwise, no attenuation).

ln this position the amplifier operates at full gain.

Turning the attenuator back (anticlockwise) reduces the input sensitivity by the amount marked on the attenuator scale (dial).

NOTE: lf full power output is required you should operate your amplifier with the front panel attenuator above the

-15d8

position, othenrise clipping of the input circuitry and its resultant distortion will occur before full output power is achieved.

Sensitivity

Youramplifier is a lineardeviceoperatingwith afixed input to output voltage gain (less attenuation). The maximum output voltage sldng is determined by the applied mains voltage, load, load type and the duty cycle of the applied signal.

The voltage gain factor of your amplifier is:

37 (31.5 dB) for a PA800

45 (33.0 dB) for a PA1200

Th e i n put sensiti vity f o r y our Pr4am/?4tzu amp

I ifi er when

the

attenuator

is at

the "O' dB position (fully clockwise) is nominally: attenuation

We

recommend tuming

the

attenuators

on

your amplifier down when turning the unit on.

When you power up you r

Pfu/Prltzu,your

ampl ifi er goes through an establishment period before it will

+4.0d8

(1 .23 volts in) for rated power into a 8 ohm load.

+3.0d8

(1

.

10 volts in) for rated power into a 4 ohm load.

Asbalian Monitor,

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l1

Operation

Each channel of your

Plw/F,hzn

amplifier has a nominal balanced

input

impedance

of

3OkOhms

(@1kHz) and should not present a diffiq.rlt load for any signal source.

Your signal source (i.e. the equipment feeding the amplifier) should have

an output

impedance of

600 Ohms or lower to avoid urnvanted h i gh freq uency loss in the cabling.

lnput overload occurs at +20.5d8u (8.25 volts).

See the specification section for more detailed information.

Hum

Problems

Most equipment is designed for minimum hum when used under ideal conditions. When connected to other equipm€nt, and to safety earth in an electrically noisy environment however, problems wi ll often ocanr.

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 radiation capacitively couples to 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 offending can usually be reduced by moving the lead away,

or by

providing additional electrostatic shielding (i.e.

an

earthed conductor wfrich forms a banier to the field).

Electromagnetic radiation induces interference currents into system elements that mainly effect lower impedance paths.

Rqdio transmitters or stray magnetic fields from mains transformers are often the cause of this problem. lt is generally more difficult to elirninate this kind of interference, but again, moving the a source away or providing a magnetic steel shield) should

help.

I shield (i.e.

Earth

loops

can arise from the interfacing of the various pieces of equipment and theirconnections to safety earth.

difference between the amp earth and source equipment earth appears to the amplifief s input as a signal and is amplified as hum.

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

1.

Ensure your mains powerforthe audio system is

"quiet" i.e. without equipment on it suclr as airconditioning, refrigeration or lighting whicfr may generate noise in the earth circuit.

2.

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

3.

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

Signal Ground-Lift Switch

When proper system hook-up has been carried out, you may still have some hum or hum related noise.

This may be due to any of the previously mentioned gremlins.

Y our

PtfutPltmampl

ifi er has a

" S ignal Ground

Liff

switch which disconnects the input ground wiring from the amplifier. A substantial drop in hum and or hum related noise can result from judicious use of this switch.

NOTE lf the input ground lift switch is used you must ensure adequate shielding of the input wiring. lf 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 "drbin" 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.

You

will

defeat

the

amplifiers intemal grounding scheme and possibily cause instabilitytothe amplifi er.

This is byfarthe most common cause of hum, and it occurswhen source equipment and the amplifierare plugged into difierent points along the safety earth where the safety earth wiring has a cunentflowing in

il

The cunent flowing through the wire produces a voltage drop due to the wire's resistance. This voltage

Always ensure that your amplifier

is off

and the attenuators are down when you engage this switch.

This switcfr should only be used when the amplifier is operated from a balanced signalsource.

NOTE: Be wary of quasi{calanced outputs, these are often no more thanfloating unbalanced outputs.

ltu

Bridge

Mode

15

5.

Bridge Mode

The term BRIDGE is used when two independent amplifier

The load channels are used to drive the same load.

is

in series amplifier channels.

(a bridge) between the two up y our

Piau/Pirzu

am p

I if i er for ru nn i n g it i n B R

I

D GE mode.

Whilst the amptifier is

ofi

1 .

Connect the signal source to the Channel-Afemale input XLR. The Channel-A attenuator becomes the level controlfor both channels.

ChannelA is used asthe "dominant', channel and its output is in phase with the input signal, and channel

B has its phase reversed so it is exacily 1g0o out phase with the input signal.

of

2. Engage the "push to bridge" switch.

As two amplifiers with a phase difierence of 1gS are now driving the load you will now have double the voltage into the load. This means you will now have four times the

porcr

into that load. The output can now be considered as an active balanced output.

3. Connect your load between the red binding post output terminals, where the positive side of the load is connected to lhe channel

A output (marked

BRIDGE+) andthe negativesideof the loadgoes to the channel

B output (marked BRIDGE-). There are no further connections required.

Acommon useof an amplifier in BRIDGE mode driving 70volt& l00voltdistribution tines. ln isfor

BRTDGE mode, The Pthzo can produce over 100 volts with line impedances over 8 ohms whilst the &Qao can produce over 84 volts with line impedances over g ohms.

Equally the units can be used in bridge mode to provide the correct voltage/power requirements for an applicable load.

As shown in Figure 6, there are three steps in setting

You can also source the output from the Channel-A

SPEAKON output connector where Channel-A will be on the pin marked

1

+ and Channel-B will be on the pin marked

2+.

NOTE: You should check after market manufactured

Speakon interconnecting speaker

leads

before connecting them to your amplifier.

Some leads are manufactured for specific purposes, or specific use, and may have pins shorted inside the connector. Any speakon lead with shorted pins willobviously short the output

of

your amplifier (either output to output - be careful)

to

ground, or

Fiox

!ilcNAL souecc

I

-

-

o

!il!

!il!

(::=f

?fftil

8fifil

-

-

-)

(-

-

-

(-

Figure

6

Bidge Mode Speaker Connection

Australian Monitor

/tu

16

Two Ohm or Not Two Ohn

6. Two Ohm

Not Two or

Ohm

NOTE:

Ensure adequate ventilation and monitor the

FAU LT indicators to guard against thermal shutdown when driving two ohm loads.

specification sheet is derived from a voltage exanrsion into

a

resistive load

for a

sine wave

at a

given frequency. Though this method is in line with the various standards that exist, it only gives an indication to the maximum voltage s,wing (before clipping) for a given load. Th is method of rating power does not give an indication of the current (Ampere) capability of the amplifier, nor does it show the amplifier's ability to sustain high energy waveforms.

A Preamble.

The load that a loudspeaker presents to an amplifier is very complex and at different frequencies can be inductive, capacitive, resistive, or a combination of these (reactive). With the these attributes, which complex interaclion of alter from loudspeaker to loudspeaker, not a definitive load for an amplifier does really exist.

Your P4au/P,'hzmamplifier is designed to be able to deliver more than twice the cunent than that shown on the specification sheet to cope with difficult loads andlor high energy waveforms.

This extra cunent reserve is the result of over engineering and is the headroom the amplifier utilizes to control the loudspeaker and dealwith the "reactive energy" from the loudspeaker load that has to be dissipated within the amplifier.

Loudspeakers operating within

an

enclosure are specified with a nominal impedance. This nominal impedance

is

only

a

rough guide

to the

load it presents to an amplifier.

As an example, a loudspeakerwith a nominal impedance of say 8 ohms, may have an impedance of over

50 ohms at resonance (bass frequencies), drop to less than 6 ohms after the resonance peak (through its mid band area) and then increaseto over 16ohms for higher frequencies.

A 4 ohm load makes an amplifier work "harde/' than an 8 ohm load at the same voltage, as double the cunent is required.

Though various loudspeakers may be marked with the same nominalimpedance, some loads are more difficult than others.

Bass frequencies usually exhibit higher impedances and require higher voltages to achieve the desired result. They also reflect higher energy back to the amplifier simply due to the amount of cone excursion involved at lower frequencies.

The Mid frequency band usually offers the lowest impedances and the highest duty cycles requiring both high voltage and high cunent.

The High frequency region usually offers a moderate impedance and usually does not need much voltage but the instantaneous current demand can be much greater than you think.

As well as this burden on the amplifier, the transient waveforms found in actual use can demand

a

lot more current than the "steady-state" sinewaves used in most amplifier bench tests.

The power output of your

PimlPhzmquoted

on the

Your

Pfu/Ptltzm

amplifier is able to drive 2 ohm loads or operate in BRIDGE mode into 4 ohms. The operator must be aware that when driving loads

or

bridged

2

ohm

4

ohm loads that

the

currents running in the output stage are very large and will

€use

greater heat build up within the amplifier than higher impedance loads.

The Front Panel FAULT lndicators can be used to provide an indication of the "difficulty" of the load and will give the operator an indication of the heat build up in the output stage.

lf the fault indicators flash with the "clip" LED or do not illuminate until well into clippingthen the load can be considered as normal or easy.

lf the fault indicator starts to flash before the "clip"

LED then the load should be considered complex and/or difficult.

For

the

more complex and/or difficult loads, the illumination of the'Yault'

LED on programme peaks should

be

interpreted

as

the

output level

limit.

Driving the output continuously past this point could result in muting of the output stage, fuse's blowing or premature thermal shutdown.

Thefault detection circuit is also thermally compensated, and fault indication will occur earlierwhen the unit is hot. lf the'fault"

LED continually lights earlier than normal, then the unit is heating up. lf the signal level is not reduced to compensateforthe heating of the unit then thermal shutdorrn may occur.

/tu

Maintenance I7

7

.

Maintenance

Y our PAau/h4tzm ampl ifi er wi ll need minimat maintenance. No intemal adjustments need to be made to the unit to maintain optimum performance.

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

Fan

Due s to the openness of the air path through your

PiwlPrhzu

amplifier, very litfle dust should setfle within the amplifier. The unit has been designed so that any dust and/or foreign particles that do setfle within the amplifierwill not unduly hinder the cooling of the unit.

holdthefan rotorstillandwipethe dust off the blades.

Many uses stall the fan and use compressed air to blowthe dust off the fan blades. lt is important to note thatthefan blades must be held stillwhilstblowing air over the blades othenrrise you may burn out the bearings in the fan.

Fuses

Alongwith rearpanel mainsfuse, there isfour(4) rail fuses provided internally in the unit. These railfuses are in series with the positive and negative output supply to each amplifier channel and provide overall protection for the output stage.

lf

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.

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

NOTE

Make sure the unit is off and is unplugged from the mains.

Give the

main

filter

capacitors

time

to discharge before removing lids and inspecting the fuses.

You should replacethefuse if theelement is sagging

or

discoloured. Only ever replace with the same type fuse and current rating.

Overtime, dust may build up on the leading edge of the fan blades

and

reduce their cooling efficiency.

The time taken forthis 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

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

Only competent or qualifi ed persons should attempt any service or maintenance of your amplifier.

Arsbdhn

I'tonitor

lfu

l8

Warranty

8. Warranty

Australian Monitorwarrants the original purchaser of each PA-Series amplifier (purchased at an authorised

Australian Monitor dealer) that it will be free from defects in materials and workmanship for a period of two (2) years from the original date of purchase.

refuse warranty service where the orner fails to take reasonable care in use and maintenance of the amplifier.

Australian Monitorwill, at its option, repair or replace any unit or component covered by this warranty which becomes defective or malfunctions under normal use and service during the period of this warranty, at no charge for parts or labour to the original owner.

To validatethiswananty, the original purchasermust complete and mailthe warranty registration card directly to Australian Monitor within fourteen days of purchase.

This warranty does not cover blown fuses, faulty fuse contacts, thermal problerns due to obstructed airflow, ordefects or malfunctions resulting from accidents, misuse, abuse, operation with the incorrect AC mains voltage, connection equipment,

modification to

faulty

or alteration

without prior factory approval or seruice by unauthorised personnel.

To obtain warranty service, the equipment should be shi pped to an authorised Australian Monitor dealer or to Australian Monitor at the owner's expense.

U n its with a def;aced seri al nu mberwi

I

I not be

aepted

forwarranty service. Any evidence of alteration, erasure orforgery of the purchase receipt will also void this wananty.

Australian Monitor accepts

no liability for

any consequential damages, whether direct or indirect, arisi ng from the use or misuse of its products.

It is the owner's responsibility to ensure that normal maintenance inspections are carried out at regular intervals as recommended in the maintenance section of this manual. Australian Monitor reserves the right to

Australian Monitor reserves the right to alter its designs and specifications at any time without notice or obligation to previous purchasers.

/fu

Australian Monitor

RANw

REG

rsrRATroN P4-seRr

ES 2

vEAR wAR

IMPORTANT

Please complete this card and return

it

immediately after unpacking the product.

This card is to be sent

DIRECTLY

to Australian Monitor.

NOTE!

Warranty is effective

ONLY

upon receipt of this card.

COMPANY

NAME

ADDRESS

MODEL

SERIAL N"

DATE PURCHASED

CITY DEALER

STATE CODE

COUNTRY

Ensure that you ftll out and send your wananty registration card.

Use fhis copy to record a duplicate of the details.

SpeciJicafion

19

Model

,

PitZOO

E.l.A

1 kHz, <0.1 06

Single

THD+N.

Sohm

channeldriven.

44OW

Both channels

driven.

400W

Pulsed @ 1 kHz, at onset of clipping,

10% duty cycle, re 4 ohms.

Single channel driven.

Both channels driven.

Bridge mode

16

8 ohm load ohm

load

1200W

Output

Impedance

@

1 kHz

<0.025 ohms

Damping Factor

@ 1

ktzre I ohms

>32o:1

Output Rise Time

(80%, leading edge of 2lkHzsquare wave)

(leading edge, 20kHz square wave

@ ctipping)

Weight

Net 37.5 tb (17kg), Shippins 43tb (19.5kg)

Model

, PIAOO

Output Power

E.l.A. 1 kHz, <0.1 %

Single channel

THD+N. Sohm

4ohm

driven. 285W

460W

Both channels

driven. 255W

400W

Pulsed @ 1 kHz, at onset of clipping,

10% duty cycle, re 4 ohms.

Single channel driven.

Both channels driven.

550W

500w

Bridge mode

16 ohm load

8 ohm load

510W

800w

Output

Impedance

@

1 kHz

<0.030 ohms

Damping Factor

@ 1 kHz re 8

ohms

>260:1

Output Rise Time

(8006, leading edge of ZOkHzsquare wave)

<2.8 pS

Slew

Rate

Sov per pS

(leading edge, 20kHz square wave

@ clipping)

Weight

Net 33 lb (15kg), Shipping 38.5 tb (17.5kg)

Common Specifications

Distortion

(0.5 dB betow ctipping re 4 ohms)

THD+N

(@

1

kHz)

IMD SMPTE (60 Hz

IMD DIM

&7

<O.O1%

kHz41)

<0.05%

30

(3.15kH2 sguare & 15 kHz) <O.O2o/o

Input CMRR

@

1 kt.i.z

(re 8 ohm rafing)

Signal ,/ Noise ratio

'A" weighted (re 8 ohm rating)

Frequencv

Response

2OHz-20k{z

-3dB points

<

r

0.15 dB

<10 Hz - 90 kHz

Crosstalk

@

1 kHz (re 8 ohm rating)

Input

Impedance

Line to Line (Balanced)

30k ohms

Dimensions

excluding handles

Input Sensitivity

(nominaily)

For rated power re 8

ohm

1.26 Vrms (+4 dBu)

For including handles rated power re 4

ohm

1.10 Vrms (+3 dBu) (19 inch EIA rack mounting,

H

xW x

D

3.5 x

19

88

x 482

3.5 x

19

88

x 482 x

14.8 (inch)

x 375

(mm) x

17.7 (inch)

x 450

(mm)

2 units high)

Test conditions

Input source = 600 ohm, Balanced and ground referenced (CMRRtest had floating ground source). Mains regulated to 240 volts

Standard production units measured. No compensation applied.

& E0 ohm

/

50h2. All measurements taken at binding posl output terminals.

Aushalian Monitor

/tu

Australian Monitor

Distributed

by:

Audio

Telex

Communications

Pty Ltd

ACN 001345.+82

Australia www.audiotelex.com

lnternational Enquiries

Ph: 61 -2-9647

1

411, Fax: 6i -2-97

48

2537, E-mail : [email protected]

Sydney

Ph: (02) 9647 1411, Fax: (02) 9648 3698, E-mait: [email protected]

Melbourne

Ph: (03) 98907477, Fax: (03) 9890 2927, E-mait: [email protected]

Brisbane

Ph: (07) 38521312, Fax: (07) 32521237, E-mail: [email protected]

'

Perth

Ph: (08) 9228 4222, Fax: (08) 9228 4239, E-mait: [email protected]

Auckland

Ph: (09) 4159426, Fax: (09) 415 9854, E-mait: [email protected]

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