Crown macro-tech-ma-5000vz Service Manual

MACRO-TECH 5000VZ

OVERVIEW

At

first glance

Series

amplifier, except that

power.

The different the

others,

representsaradicaldeparturefromthe"normal"Crowndesign.

chapters covered

MA-5000VZ

the

internal

from

other models

but

with a f

as a

MA-5000VZ

structure

ew

more f eatures.

the

"normal," this chapter

unique

entrty.

looks a great deal

¡t is

physically larger

of the

in the MA

MA-5000VZ une.

To the

technician,

shall

endeavorto

Hke any

and

puts

is,

however, quite

user, this

this

other

out

more

one is

amplifier

Notes

MA

like

the

The

amplifier power overloaded power phenomena,

The

unit

turn-on

DC

on the

sense, A

mode Loudspeaker Offset Integration (LOI). on,

prevenís audible frequency range. The

low

35

Hz

(Butterworth

order

Bessel

A

compression

on

fast eilherinputoverloadord¡stort¡on(cl¡pping). (operates

Thefour-quadrant

Ihe

grounded bridge patentad load which

The

grounded bridge

texl.

¡s

protected

amplifiers, including

supplies,

input-overload

protects

and

outputs. Additional protection features include input current

overvoltage

of

frequencies

by

swilches as a

lopology

loudspeakers

turn-off

protection which

excessive bass frequency

response).

response

circuil

peak

lopology

also

are

twice

from

all

common hazards that plague high-

shorted,

excessive temperature,

damage,

from

transients. (AC

are

and

in

on

Ihe

limiter).

and

makes

the

is

covered

It

mains).

may

It

operates essentially

rolled

off at Ullra-sonics

-3dB córner

each channel

rear panel. This compressor

used

makes

peak-lo-peak

vollage

open

and

DC in the

also

detects

be

switched

The

18dB/oclave

may be

in the

grounded

full

use of

any

output

in

detail

or

mismatched

chain-destruction

high-frequency blowups.

input

signal

and

prevenís

on or

LOI

circuit, when switched

cone

excursions

as a

with a -3dB

are

rolled

of

SOkHz.

switched

Compression ratio

oulpul

Ihe

power supplies. This

voltages

device

in the

¡s

BASICS

unwanted

off

is

below

band-pass filter.

córner

off

wilh a second

off,

on

is

aclivaled

is

slages

available

ever exposed

seclion

loads,

from

called

the

slow,

infinite

is

called

lo

the

of

this

of

or

by

to.

MA-5000VZ

- 1

Notes

The

two

channels

may be

used together

to

double mono)orthecurrent(parallel-mono)presentedto gives

the

User

Output AC

mains):

flexibility

power

of the

StereoSohm:

Stereo4ohm:

Stereo2ohm:

Bridge Bridge

Mono 8 ohm: 4000W Mono 4 ohm: 5000W

in

maximizing

amplifier

1300W/CH

2000W/Ch 2500W/Ch

is

rated

the

power

as

follows (assumes

Parallel Mono 2 ohm: 4000W Parallel Mono 1 ohm: 5000W

the

voltage (bridged-

the

load. Thisfeature

available

to the

120V

load.

60Hz

MA-5000VZ: CHANNEL1

SHOWN

Macro-Tech amplifiers

state

of the art

and

results

Aluminum amplifiers

measured

technology

compensation

¡n

ultra-low

extrusions

due to

on a

watts

doesn't

technology developed

Our

thermal provides power

diffusers

an

extremely high ratio

devices

are

utilize a wide

distortion

have

their

low

per

perform

for are

mounted directly

electrically hot. Making

bandwidth

techniques.

This produces ideal behavior

multiloop

valúes.

been widely used

cost

and

reasonable performance. However,

pound

or

watts

nearly

as

per

volume

well

for

heatsinks

basis,

as the

Macro-Tech power amplifiers.

fabricated

the

heat spreaders electrically

of

área

to

from

custom

to

volume,

massive

cut fin

or

heat

spreaders that

design with

the

thermal

área

to

4

(ooep)

in

power

extrusión

diffuser

stock

weight.

hot

allows

that

All

are

MA-5000VZ Overall

Diagram

Block

2 -

MA-5000VZ

D

(ODEP)

improved thermal performance underneath thermal circuit,

Air

flow Macro-Techs. was

covered

the

MA-5000VZ ODEP circuit

in

the

power devices.

and

this

amplifier

Fan

speed

in

detail

maximizes utilization

is

front

is a

in the

BASICS section

by

eliminating

The

chassis

to

rear,

function

are

unique

the

insulating

itself

is

used

of the

available resources.

also a departure

of

ODEPIevel.

of

this text,

and

will

be

interface

as

part

of the

from

other

AlthoughODEP

the

specif

ics of

covered here.

Notes

The

MA-5000VZ,

does

differ,

four

devices

stages

are

OUTPUT

like

other Macro-Techs, uses

however,

¡n

also physically

in

parallel

STAGE

certain

ratherthan

built

CIRCUITRY

aspects.

the

in a

For

normal máximum

modular way,

replacement.

Electrically, there consist one side protective

of two

set for low

by

stealing

action

accomplish Circuitry

circuitry, limit),

on the

current

last

voltage amplifiers (LVA's), pre-driyers, drivers, devices. Temperature the

output modules. These deliver ¡nformation

which

computes actual calibrated temperature

temperature

are

also

a few

transistor devices

per Vbe

side). Also, ODEP affects

low

side

bias

and

which

the

same thing

positive limit

limits,

by

and

circuitry

sensors

mutes,

stealing drive.

negative output modules ¡nclude bias

(the MA-5000VZ

are

measurement.

H-15V

differences.

multiplier (one

the low

drive. Taking that a step further,

or

shuts down

also mounted

the

grounded bridge.

example, quadrants

of

three. Output

for

ease

of

Bias servo networks

set for

high side,

side

as

well

as the

the

amplifier will

has two

to the

for

speed current

and

output

heatsinks

main

module

ODEP

It

use

field

high

any

vía

and

R571

2.7K

U50O

LM334

The

positive

of

the

voltage translator stage

High

Side

to

the

very

L

V.

r

r£

227

LVA's

(HS) predriver. There

high requirements) that mode.

D522

prevenís to the HS NPN

stage.

3

(Q501,

voltages are

present

the

Positive

R572

O.5OW

(NPN) Output

Thermal

Sensor Circuitry

R584

2.7K

\

Q502,

and

Q503)convert

to a

positive drive voltage

are

three

LVAtransistorsin

(therefor

when

+LVA'sfromproducinga

higher

the

power

current

supply

Stage

+TEMP1

the

:

negative

output

for the NPN

parallel

and

thermal

is in

high voltage

high negative output

MA-5000VZ

- 3

due

Notes

Q507, Q508,

to

the

+LVA's,

On

the

slew

rate.

through

and

Q509

¡ncluding

positive side D514, D515,

D514

and

D515

the

LVA's.

D516,

image. Q534

and

Q540

provide

Sense

lines

are

arranged such that excessive current through

HS

output device

are

the

negative side mirror image.

Q503

on the

will

result

positive output module works negative output module with great Potentiometer R505 easily measured Refer

to

section

stabilily,

2 for

control

is

from

are the

-LVA's

and are

arranged

D513.

and

C506

vía

the

also

prevent dangerously excessive current

D517,

and

C507

are the

two-speed current limiting

in

current limit protection. Q535

in

tándem with Q505

as a Vbe

biasforthe

used precisely

pin 2

multiplier

(hot)

to pin 4 of ATE

circuit.

High Side

set

NPN

bias voltage. Bias voltage

appropriate test procedures.

¡n

mirror

image

+LVA's

negative

¡n the

act to

limit

HS

mirror

output stage.

any

single

and

Q541

on the

They produce and,

and

PNP

devices.

is

ports

TP1 and

TP2.

Q504¡stheHSNPNpre-driverandQ511 devices

are

biased

class

AB for

ultra

low

región. Q513, Q515,

devices driver, they function work

¡n

referred engineers free

method used today.

Q517,

are

biased

parallel

to as

in

1966.

Positive &

Positive

and

class

as a

giant composite.

AB+B,

originally conceived

This

LVA,

Current

Q536

are the HS NPN

B, in

soft

cut-off,

three-deep Darlington.

The

¡s

still

the

most

Portion

Limit

R595

82K

C536 O.O01

of HS

Section

D51O

3

r-

istheHSNPNdriver.

distortion

in the

zero-crossing

output devices. These

Together

efficient,

Bias,

The

over-all

and

patented

stable,

with

driver

output devices

bias topology

and

VCC1

These

and

by

Crown

distortion

pre-

is

High Side and the

portion Network Module.

+LVA's,

on the

Current

of the

Bias

Limit,

Servo

Positive Output

4 -

MA-5000VZ

HIGH)

SIDE

BIAS

R5O5

500

';

U

Emitter Output

Sense Audio

D506

is

theflybackdiode that a back flyback

diode

EMF

will

output devices.

PNP

pre-drivers,

mirror

image

of the NPN

forthe

HS NPN

output quadrant.

In

the

(flyback) pulse exceeds power supply voltage,

shunt this voltage

drivers,

output devices,

to the

supply

and

in

order

flyback diode D508

to

protect

side.

event

the

are a

Notes

Overall

stage, The LS

The are balance driver

LS transistors, Q529 pin

R556

Diodes D504 the

Q527

in

¡s

ground reference

LS

When

a

the

High

Side

of

bridge operates much

but the Low

senses output voltage

audio output

static

and

of the

circuits

bias

¡s

controlled

Side

(LS)

is

quite unique.

and

common

is

inverted

by

U503. dynamic balance controls. grounded bridge. Output

through

and

the LS

in a

Q530,

bias network.

fashion

along

similar

fix LS

Also

of the

15(hot)topin13ofapplicableATEportTP1

adjusts

bias transistors signal

(NPN) the LS that

rather

PNP's conduct,

the

dangerous thermal

bias

in the LS.

and

D505 control

and

Q528 (PNP).

opérate

class

AB+B,

than driving a load,

for the

and

high

vice versa

polarity

¡s

delivered

Pre-drivers,

exactly

the NPN and PNP

voltage

(as

to the

like

rails.

explained

ODEP circuit senses that limiting drive

condition,

¡t

provides

like a conventional output

(ground) buss potential.

in the

U503 input

These

bias voltage

controls provide a fine

op-amp

to

drives

that

of the HS. Two

as

measured

orTP2. Potentiometer

of

applied

the HS. The

bases

drivers,

LS

drive signal.

of the

and

output devices

major

stages control

As the HS

is

an

output which limits drive

NPN's conduct,

in

section

necessary

circuitry

the LS

pre-

from

Via

pre-drivers

difference

the

4.2.1). to

prevent

+

LVA

+VCC1

C5O6

220pF

_L

OUTPUT POSITIVE SECTION

+VCC

Q513

Q515 Q517

C510

'

O.O1

MA-5000VZ

BUSS

BAR

- 5

Q536

H-VCC1

'

D5O6

High Side Predrivers, Drivers, and Notice lines. for such

Output

Flyback Diodes.

the

These

various functions

as VZ sense and features.

Devices,

various sense

are

used

switching

protection

To

NPN LS

Predriver

-I-VCC1

o

J

D5

D4

y

H

C524 2OOpF

D521

N

d

I-15V

R552

1OO

D518

A

I

^

D5£

5

r

os:

5

C52

6 =

10p

— <

RS56

500

4

1

f

LOW S

DE

>>[

BIAS

Low

Side

Low

Side Bias

circuit which clamps

protective function.

R554

1

'

R555

>

1K

of

I-15V

R553 1OO

k

4

_L

l

C528 33OOpF

1

'

C534

!47pF

R547

4.99K

C52S

xH

U5O3 LM6364

JjH

OUT1

I

COMM1

1

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—

B

.821

6

R56O

<

47K

Bridge: sensing amplifier output

(portion

on

positive output module),

Low

Side signal

¡n the

and

event

¡nverting

and

differential

of

ODER

the

or

15V

signal, other

I

¡T

D507 > 12

rNr^^>1^J

LLL

+VCC1

>

H534

X

2W

r-

0.022

l-t

Ql

C520

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ice; n A

S

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Q525

L

Q538

V|

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tí

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R536

>

0.33

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S

R538

>

0.33

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Q523

/

R54O

0.33

5W

i

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R542

4.

0.350W

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-

R544

51

100

r^^V^VN

R546

Low

Side

of

Driver, Output Devices,

Diode

on the NPN

C522

0.033

ni

+VCC1

Q527

kr

.

R550

13K

||

Bridge: including

and

side.

P

Fl^

6 -

MA-5000VZ

to

the

output

main module

(via wires

labeled

devices. This

(LS

NPN

quadrant),

POWER

TRANSISTOR

SPEAKER

LOAD

POWER

TRANSISTOR

POWER

TRANSISTOR

SPEAKER LOAD

stages.

and

is

For the HS,

isexplained

±LL) a signal

this

limiting

¡nsect¡on4.4.

which

limits bias feed

¡s

accomplished

Forthe

LS,

accomplished through current mirrors Q532

and

Q542

and

Q543

(LS PNP

VZ

POWER

The VZ supply in the MASOOOVZworks, much

like

the

sake

of

some

conceptual things

duplicated VZ

means and is the patented

here. Variable Impedance

ñame

articulated

supply technology.

VZ

POWER

SUPPLY

Crown power vertical

A enough voltage for máximum rated power into specified load. of

to

pack tremendous

into just 5.25 inches

rack

power supply must

to

handle

and

the

amplifier

fulfilling this requirement cónventional power supply designs produce are

VZ

STAGEVZSTAGE

heavy,

real

that heat

and

estáte.

is one of a

amplifiers worst enemies.

on the

ODEP provides

to the LS

and

output

Q531

quadrant).

SUPPLY

inconcept,

MA-3600VZ.

completeness,

will

of

Crown's

power

It

enables

space.

be

large

the

máximum

current

And

to

In the

lots

take

up

it's

necessary

drive

process

of

heat,

precious

no

secret

power

Notes

very

For

be

of

its

a

POWER TRANSISTOR

Low

Voltage, High Current Mode

VZ

POWER SUPPLY

POWER

TRANSISTOR

SPEAKER

LOAD

POWER

TRANSISTOR

High Voltage,

Low

Current Mode

VZ

STAGE

VZ

STAGE

According bigger

more must

the

resistance transistors, you

at

the

resistance you

to

Ohm's Law,

the

power supply,

heai

the

power

dissipate.

Also,

of the

the

can

deliverto

same time that

of

increase

passing through

again ¡ncrease

heat

they must dissipate.

An

articulated power

like

VZ, can

of

this problem

voltage

when

appliedto

less

the

circumvent much

by

voltage

MA-5000VZ

the

transistors

the

lower

power

more voltage

the

load.

But

you

lower

the

transistors,

the

current

them,

and

amount

of

supply,

reducing

the

is

the

transistors

required.

- 7

Notes

Reducing you can

the

voltage

safely pack more power into

reduces

the

heat.

Since

the

chassis.

amplifier

runs

cooler,

The VZ current signáis

For This time.

The are

more current. The

dissipate supply.

When to

never doesn't need

Sensing

supply

requirements

like

music

means a power supply does

VZ

supply

not

high,

power transistors

Ihe

produce higher

misses a beal

GROUNDEDBRIDGE

OUTPUT STAGE

is

music

the

average

is

it

opérales

heal.

vollage

¡t.

circuilry

divided ¡nto segments

of the

power transistors. Remember that audio

are

complex waveforms.

level

is

always

not

divided

This

walches

into

two

in a

parallel mode

slay

cooler

is

Ihe

normal

requiremenls

vollage

and

gels

Ihe

parís.

are

less

full vollage when

vollage

to

better match

much

need

to

When

and are

operaling

high

VZ

currenl.

of

Ihe

the

voltage

less

than

the

peak

produce full voltage

the

voltage requirements

to

produce less vollage

nol

torced

mode

swilches

The

amplified

it

signal

needs

lo

needlessly

of

Ihe

to a

series mode

oulpul

il—not

lo

delermine when

VZ

Power

Supply

VZ

and

level.

all

the

and

power

signal

when

il

^

Input

8 -

MA-5000VZ

R = Switch

Resistance

to

switch audible function—you only power

Actual together

The transformer, start VZ supplies series

VZ

modes.

switching

the

máximum power with

matching

current

is

shown

individual

circuitry taps

Control circuitry senses

to

either parallel (high current) mode

(high voltage) mode

distortion

hear

to

your load.

flow

with power supply

on the

components

though

in to

The

switching

only

the

previous page.

are

not

shown,

control

audio

for

circuitry

to

yield

the

musió

and not the

the

máximum safety,

and

shown is

AC

high program peaks.

below.

where shutdown protection

mains ¡nput

level

and

is

highest dynamic transfer

amplifier.

grounded bridge operating

Upstream

to the

switches

for

designed

You get not

you

also

power

the

articulating

lower

level audio,

to

prevent

get

the

of the

and

supply.

Notes

best

toroid

soft The

VZ

or

Toroid

In

both examples

the

dual

is

sensed

and at

about

(the

switch

No

current

as

shown MOSFET switch. Since same time, positive side

mode.

Like

series mode, double current

Bridge

1

it can be

supplies

via a

for

are

torced

line

tapping

80% of the

is

actually a three-device

will

flow through either

channel

and the

of

Bridge

two

batteries,

parallel

1)

because reverse polarity

this

negative side

2, the

seen that

to

off the

happens

supplies

the

¡n

when

the

MOSFET switch

opérate

supplies will provide double voltage

parallel mode.

¡n a

parallel mode. Audio level

NFb

loop.

When audio level

mode supply voltage,

composite switch)

of the

control diodes to

both rectifier sources

of

Bridge

are

1 ¡s

forced

(D810

is

applied through

then to

opérate

the

are

shorted

is

off,

¡s

rising

MOSFETs

turned and

at the

to the

in

series

on.

D811,

the

in

Although switch

modes

opérate

shipped

the

supply

to

from

the

factory

lock

low

voltage (high current),

in

Bi-ODEP mode. Bi-ODEP

¡n

normal

VZ

mode, lock

high voltage,

is

similar

MA-5000VZ

the

to

user

normal

- 9

may

or

VZ