Crown SR-2, Studio Reference Mk1 Service manual

PROFESSIONAL

STUDlO

AMPLIFIERS

Studio

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8

.

.-

1

Bntroductisn

1.

1

The

1.2

Scope

1.3

Warranty

2

Specifications

2 . "Berformance

2.2

Pswei

23

Cantrofs

2.

4

f

ndicators

2.5

l~putsautput

2.6

Output

22

Protcctisn

2.8

Construction

3

Va1tags

4

Circuit

Conversion

Theory

4.1

Overview

4.2

Features

4.3

Frant

4.3.1

4.3.2

4.3.3

4. 4

Voltage

4.4.1

4.4.2

4.5

Grounded

4.5.

Wigh

4.5.2

4.6

Output

4.7

Ganliol

4.7.1

4.

7.2

4.7.3

4.7. 4 Fan

4.8

Power

4.8.

1

423.2

4.8. 3 Over

4.9

Display

4.9.1

4"9+2

433

Studio

...................................................................................................

Stndis

Referents

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............................

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.................................................................................................

.............................................................................................

..........................................................................................

Signal

..........................................................................................

........................................................................................

.................................................................................................

...........................................................................................

.............................................................................................

End

Operation

Balanced

Variable

Error

Amp

Amplification

Voltage

bast

Voltage

Bridge

Side

Law

Side

Device

Circuitry

DC$LF

fault

Turn

AC

Soft

Protect

Circuit

On

Corjtrol

Supply

kine

Start

Voltage

Circuitry

............................................................................................

1QC

ODEP

Signal

........................................................................................

Indicafis~s

Reference

........................................................................

...................................................................................... 2.

Service

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Manu3l

@crown

3-1

1-1

-2-1

1

2-1

2-2

2.2

......................................................................................

.....................................................................................

......................................................................................

..........................................................................

Gnin

Stage

Gain

Stage

(BGS)

(VGS)

.....................................................

........................................................

..................................................................................

.........................................................................

Transfators

Topology

(HS)

(LS)

Emulation

................................................................................

....................................................................

Amplifiers

.........................................................................

............................................................................

(LVAS)

...............................................................

Prccalectian

..................................................

(OBEP)

....................................

............................................................................

...............................................................................

Belay

...........................................................................

................................................................................

....................................................................................

Fiiter

............................................................................

...................................................................................

Protection

............................................................

..............................................................................

........................................................................

2-3

2.3

3-1

4-4

4-1

4-2

4.2

4-2

4.3

4-3

4-4

-4-4

4.4

4-5

4-6

4-6 4-6

4-6

4-7

"4-7

4-7

4.7

5

Electrical Checkout

51

General

52

Standard

53

DC

Offset

5.4

Output

55

OBEP

5.6

AC

Pawer

5.7

High

5-8

Common

5.9

Voltage

533

Level

5.

1

Current

512

Slew

.

5

f

3

Crosstalk

5.

1-4

Output

5.1

5

Reactive Loads

5.

16

ODEP

5%

17

Mute

5.

18

Law

5.

19

Signal

5.20

Intermadulation

5.21

LED

5.22

Display

5.23

Turn-On

5.24

Turn-OM

525

Past

6

Schematics

7

Parts

7.

7.2

7.3

7.4

7.5

7.6

Figure

Fi%jure

Figt,i

Figure

....................................................................................................

Information

1

General

Standard

Ordering

Shipment

Terms

Illustrated

7.1

7.2

7.3

7.

4

7.5

re

7%

7.

7

...........................................................................................................

and

Adjustment

Informatiow

Initiat

...........................................................................

Conditions

..........................................................................................

Bias

Adjustmen$

Voltage

tine

Gain

Controls

Rate

Adjustment

Draw

.................................................................................

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Mode

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bimi

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....

...............................................................................

and

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Power

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Limiting

and

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to

Functions

Set-Up

Transients

Transiep-rts

Testing

.................................................................................

Turn-On

Noise

Delay

Protection

Ratia

Diskoflion

.................................................................................

................................................................................

...........................................................................

..........................................................................

.....................................................................................

Procedures

................................................................

....................................................................

.................................................................

,,,

.......................................

5-1

..................................................................

5-1

5-2

Wave

....................................................

5-2

5-3

5-9

5-3

5-4

..................................................................

...............................................................

.......................................................................

...............................................................

5-4

545

5-5

5-5 5-5 5-5

6-1

............................................................................................

lnfarmation

and

Parts

....................

...........................................................................

Special

Parts

...............................................................

...................................................................................

.....,.

........................................................

.................................................................................................

Parts

Front

Panel

Top

Main

Bottom

Back

Output

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PIP

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Assembly

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7-1

7-1 7-1

7-7

7-1

7-2

7-4

7-6

7-8

3-1

61

7-12?

7-15

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Module

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8.1

General

8.2

Studia

8.3

Studio

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8.7

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8-28

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2.1

3.1

32

4

4.2

43

5.

5-2

53

5.

56

5-4

7.

4.

7.3

7.

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8.2

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Q43363-8

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Breaker Selection

Studio

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kHz

Square

Load

Yest

Waveform

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Panel

Parts

Main

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Main

Panel

Assembly

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Cage Assembly Parts

-6

Main

Output

Control

8-3

Bispray

1-2

Main

Output

Display

Reference

Dimensions

Wiring

Refereilea

Front

Bridge

Circuit

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2-3

3-1

3-11

4-1

..

4-3

4-5

5-2

5-3

5-4

7-2 7-4

7-6

7-8

7-16

F.12

7-14

8-7

8-18

8-13

8-16

8-19

8-22

8-27

8-32

8-35

8-38

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Specifications

2-3

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Studio

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Voltage

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Studio

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Manual

INVERTING

BRIDGE

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innovations, including gf@tuflded teehnofogies.

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Electrical

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5-6