Dolby Laboratories SR 280 Bedienungsanleitung

[](I

DolbY

SR

Cat.

No. 280

Spectral

Recording

Module

User

Information

USER

INFORMATION

FOR

SPECTRAL

RECORDING MODULE

CAT. NO. 280

Dolby

Laboratories

Incorporated

U.S.A. 100

Potrero

Avenue,

San

Francisco,

CA

94103

Tel: (415) 558-0200; Telex: 34409;

Fax:

(415) 863-1373

U.K.

346

Clapham

Road,

London

SW9

9AP

Tel: 01 720-1111; Telex: 919109;

Fax:

01 720-4118

WARRANTY

INFORMATION:

Equipment

manufactured

by

Dolby

Laboratories

is

warranted

against

defects

in

materials

and

workmanship

for

one

year

from

the

date

of

purchase.

There

are

no

other

express

01'

implied

warranties

and

no

warranty

of

merchantability

or

fitness

for a

particular

purpose.

During

the

warranty

period

Dolby

Laboratories

will

repair

or,

at

its

option,

replace

components

which

prove

to

be

defective,

provided

the

unit

is

shipped,

prepaid,

to

the

manufacturer

directly

or

via

an

authorized

distributor.

Defects

caused

by

modifications,

misuse

or

accidents,

and any

further

damage

caused

by

inadequate

packing

for

service

return,

are

not

covered

by

this

warranty.

Dolby

Laboratories'

obligation

is

restricted

to

the

repair

or

replacement

of

defective

parts

and

under

no

circumstances

shall

Dolby

Laboratories

be

liable

for

any

other

damage,

either

direct

or

consequential.

All

requests

for

repairs

or

information

should

include

the

unit

serial

number

to

ensure

rapid

service.

ill1986

Dolby

Laboratories

Inc.

S871741717493

This

information

is

intended

to

serve

as

an

introductory

user's

guide

for

the

Cat.

No. 280

spectral

recording

module.

It

assumes

of

the

basic

principles

of

audio

recording,

complementary

signal

processing,

and

some

familiarity

with

Dolby

A-type

noise

reduction

and

interface

frames.

Important

Note

The

Cat.

No.

280

spectral

recording

module

is

both

and

level

compatible

with

the

Cat.

No.

22

A-type

module.

In

most

cases,

the

Dolby

A-type

user

can

simply

replace

the

Cat.

No.

22

module

with

the

Cat.

No.

280

module

and

continue

recording

using

established

studio

procedures.

(A

switch

on

the

rear

of

the

Cat.

No.

280

must

be

set

to

the

appropriate

frame

type.)

Dolby®

Cat.

No.

280

Spectral

Recording

Module

The

Cat.

No.

280 module is the

first commercially available

embodiment

of the

new

spectral

recording process developed

by

Dolby

Laboratories.

The

module

has been designed for ease of instal-

lation

in

existing 360-Series

and

M-Series frames from

Dolby

Laboratories.

Dolby

spectral recording

is

a

new

audio recording technique

which provides audible signal

integrity superior to

that

of

any

other

recording

method

in use.

The

performance of

Dolby

SR

with

contemporary

analog professional

tape recorders stands

up

to ex-

tensive scrutiny.

The

Cat. No. 280

module has been designed to allow

easy operational use of the

Dolby

SR process, using existing frames,

with

no

major

studio equipment

changes

or

capital expenditure.

Auto

Co",pare

DOlbY

••

Noise

Ref

Ta

pe

The

Cat.

No.

280 spectral

recording

module

utilizes function

logic similar to

that

of the

Dolby

Cat. No. 22 A-type noise reduction

module; consequently the control

facilities of 360, 361

and

M-Series

units operate normally, such as

IN/OUT, RECORD/PLAY

and

input

/output

gain controls.

Dolby

SR modules incorporate

a

new

recorder alignment

and

verification tool called

Auto

Compare

. A built-in

pink

noise

generator in the module applies

bursts of noise (Dolby Noise) at a

calibrated level to the recorder.

The signal is used

at

the

head

of a

tape to identify the use of

Dolby

SRI

and

to assist in recorder cali-

bration

(however, the spectral

recording process

is

more tolerant

of

input/output

gain errors

than

Dolby

A-type noise reduction).

During playback, the

Auto

Com-

pare

circuitry automatically alter-

nates the

monitor

output

between

the

Dolby

Noise off-tape

and

the

DD

DoibySR

internal noise generator. LED

indicators

on

the module front

indicate the current

monitor

con-

dition.

Auto

Compare

assists in

recorder set-up alignment,

but

additionally provides a

rapid

method

of checking a recorder

track

by

ear

during a session.

Dolby

Laboratories

has

de-

livered over 80,000 Cat. No. 22

noise reduction modules through-

out

the

world

,

and

this widespread

availability of interfaces accepting

the Cat.

No

.280 modules will

facilitate

adoption

of the

new

Dolby

SR process.

Other

Dolby SR configurations

are available, including

the

Cat.

No.

431

, a module for Dolby SP-

and

XP-Series units.

In

addition,

two testers are available to assist

process evaluation

and

module

performance verification.

Full descriptive information

about

the

Dolby spectral recording

process,

and

product

leaflets

describing other Dolby

SR

modules

and

testers are available

on

request

from Dolby Laboratories.

Dolby®

Cat.

No. 280

Specifications

INTERFACES:

The

Cat. No. 280 module can be installed

in the following frames:

Models 360 and 365

All

module

functions available, including

simultaneous

record/play

Auto

Compare

if

two

Model

360s are used in dedicated

Record

and

Play

modes.

Model

361

Auto

Compare

functional

durin

g

tape-playback following recording,

but

not

during

simultaneous recording.

M-Series Units

Simultaneous

record/play

Auto

Compare

.

The

Cat. 280 requires a special top cover

(Cat.

No

. 359) to fit in Channels 2, 10,

and

18 of M-Series interface.

CAT.

NO.

280 MODULE

SPEGFICATIONS:

Layout:

A

pair

of printed circuit cards

mounted

togeth

er

form the module. Signal

input/

output

and

control functions compatible

with Cat. No. 22 noise reduction

modul

e.

Input Circuit:

680 k

ohms

unbalanced, 300 mV rms for

reference leve

l.

Peak Encode Input Level:

3.0 V rms (20

dB

above

reference level).

Peak

Decode

Output Level:

3.0 V rms from

Output

1,

5.0 V

rms

from

Output

2.

Line Amplifier:

When

mounted

in interface,

maximum

output

+ 22

dB

into bridging load, +

21

dB

into 600

ohms

(0

dB = 0.775 V rms).

(A 6 dB higher level is possible using

+ 36 V line-amplifier supply voltage.)

Overall Frequency Response:

± 1 dB, 20

Hz-20

kHz

(encode/decode).

Bandwidth Limitation: Control Inputs:

Internal filters: 10

Hz-50

kHz. External + 18 to + 30 V to actuate record

Overall Harmonic Distortion:

mode

(provided in interface).

External single pole switch for process

2nd

&

3rd

harmonic

each 0.3%

at

3 dB

in/out

(provided in interface).

below

peak

level, 20

Hz-20

kHz. External single pole switch for

Dolby

Negligible higher

order

distortion com- Noise

mode

(provided in interface).

ponents

at

any

level. Internal three position switch to adjust

operating logic to

Models

360

and

365,

Overall

Dynamic

Range

of

Model 361,

or

M-Series interfaces.

SR

System (typical}:l

105

dB-clipping

level to

CCIR/ARM

Stability:

noise level. System

is

highly stable-does

not

require

93

dB-clipping

level to CCIR Rec. 468-2 routine alignment (no adjustable internal

weighted noise level. controls).

105

dB

-clipping level to NAB

A- weighted noise leve

}2

Operating Temperature:

95 dB -clipping level to unweighted noise Up to 45 degrees

C.

level, 20

Hz-20

kHz.3 Construction:

Typical Obtainable Dynamic Fiberglass printed circuits, solid state

Range,

15

ips: devices

throughout;

clear anodized

90-95 dB.

aluminum

covers, black characters.

Matching Between Units: Size:

±1

dB

at

any

level

and any

frequency, 192 x155 x 20

mm

(7.6

x 6.1 x 0.8 inches).

20

Hz-20

kH

z.

Weight:

Signal Delay: 500 gm

(18

oz.).

Approximately

7.0

J.l.s

per channel,

14

J.l.S

overall, encode/decode, plus delay Power Requirements:

of interfaces used.

SR

circuit:

+20

V to

+28

V,

100-140 mA.

Line amplifier:

+18

V to

+36

V,

13-17 mA.

Calibration Facilities:

Dolby

Noise

generator

for establishing

correct levels

and

frequency response, via D[] Dolby

built-in meter amplifier

and

interface

meter.

Output

signal

can

also be fed to

external analysis facilities.

Automatic

audible

Auto

Compare

function, allowing

Dolby

Laboratories

Inc.,

100

Potrero

Avenue

,

San

Francisco,

CA

94103-4813,

comparison

of

Dolby

Noise from tape Tel

ep

h

one

(415)

558-0200,

Telex

34409.

with

internally generated reference

346

Clapham

Road,

London

SW9

9Ap,

pink

noise. Tel

ep

h

one

(01)

720

-1111, Telex 919109.

"Dolby"

and

the

double

-D

symbo

l are

trademarks

of

Status Indicators:

Dolby

Laboratories

lic

en

sing

Corporation.

5871741717493

Yellow LED

on

front of module indicates

Specifications

subject

to

ch

ange

without

notice.

Dolby

Noise mode,

Auto

Compare

Reference/Tape function

status indicated

by

red

and

green LEDs

on

front of module.

(LED control signal available for remotely

situated LEDs

or

lamps.)

1.

Processor

a

lon

e; in interfaces,

may

depend

on

line

l

evels

u

se

d.

2.

Weighting

filter

supplemen

t

ed

by

25

kHz

4-

pole

low

-

pass

filter

to

ensure

that

only

audible

nois

e is

measured.

3.

Rms

or

average

responding

meter,

4-pole

filters.

SECTION

1

II

TABLE

OF

CONTENTS

INTRODUCTION

1.1 Dolby

Spectral

Recording.

1.2 Dolby

SR

Packaging

. .

1.3 Dolby

SR

Compatibility

.

1.4 Dolby SR

Calibration.

.

1.5

Cat.

No. 280

Applications.

360

Series

M-Series .

SP/XP

Series

. . . . . . . .

Cinema

Products

(CP50,

CP100,

CP200)

Page

1-1

1-2

1-3

SECTION

2 CAT. NO. 280

INSTALLATION

2.1

General

Installation

. . . . .

2.2

Configuration

Switch

and

Indicators

2.3

Interface

Frame

Switch

Labeling

2.4

Optional

External

Connections

2-1

2-2

2-3

SECTION

3 CAT. NO. 280

CALIBRATION

3.1 Dolby

Noise.

3-1

3.2

Auto

Compare

. 3-1

3.3

Auto

Compare

Control

3-2

3.4

Auto

Compare

Metering

3-2

3.5

Auto

Compare

Synchronization.

3-2

3.6 DolbyTone

and

the

Cat.

No. 280 3-3

SECTION

4

SYSTEM

ALIGNM(i:N'I'

4.1

General

System

Alignment

. 4-1

4.2 Recording

Levels

for Dolby

SR

4-1

4.3

General

Alignment

Using

VU

Meters

4-2

4.4

Using

VU

Meters

with

High

Level

Reference

Tapes.

4-3

4.5

Aligning

with

Peak

Program

Meters

4-3

SECTION

5

PRACTICAL

OP~:RA'I'ION

APp(i~NnIX

A

APP(i~NUIX

B

5.1 Model 360

Operation

. . . .

5.2

Auto

Compare

in

the

Model

360

.

5.3 Model 361

Operation.

. . .

5.4

Auto

Compare

in

the

Model 361 .

5.5

M-Series

Operation

5.6

Auto

Compare

in

the

M

Series

Technical

Aspects

.

Optional

Cat.

No. 280

Connections.

5-1

5-2

5-3

5-5

5.5

A-I

B-1

1-1

1.1

Dolby

Spectral

Recording

SECTION 1

INTRODUCTION

Dolby

spectral

recording,

or

Dolby SR,

has

been

developed to

answer

the

needs

of

modern

professional

recording.

The

Cat.

No. 280

SR

module

is

the

first

implementation

of

this

new

recording

process.

It

can

be

used

in

existing

interface

frames

manufactured

by

Dolby

Laboratories

and

will,

therefore,

allow

a

widespread

introduction

ofthis

new

high-quality

recording

format.

1.2

Dolby

SR

Packaging

To

facilitate

easy

interchange,

the

Dolby

SR

circuit

has

been

packaged

in

the

same

card

profile

and

out

as

the

familiar

Cat.

No. 22 noise

reduction

module.

This

will

allow

the

process to be

conveniently

used

in

commonly

available

360-

Series

and

M-Series

interface

frames.

The

Cat.

No. 280

cannot

be

used

in

the

SP

unit

due

to

incompatibilities

with

the

Cat.

No.

230

carrier

card.

A specific Dolby

SR

module,

the

Cat.

No. 431,

will

be

available

for

the

existing

SP-

and

XP-Series

multi-track

frames.

While

the

Cat.

No. 280

is

generally

compatible

with

the

Cat.

No. 22

module,

there

is

one

major

difference:

the

standard

Cat.

No. 280

module

is

physically

thicker

(about

.15

inch,

3

mm)

than

the

Cat.

No. 22,

and

therefore

will

not

fit

in

some

existing

Cat.

No. 22

applications.

To

address

situations

where

the

Cat.

No. 22

cards

have

been

mounted

close

together,

such

as

in

the

Model

362,

a

special

packaging

adaptation

of

the

Cat.

No. 280

has

been

developed,

the

Cat.

No. 280-L.

This

long

but

thin

adaptation

extends

the

Dolby

SR

circuits

forward

of

the

front

panel

by

about

7

112

inches,

or

190

mm,

thereby

allowing

Dolby

SR

modules

to be

used

in

close-pitch

situations.

The

increased

thickness

of

the

Cat.

No. 280

will

not

allow

standard

modules

to fit

in

a few

channels

of

the

M-Series

frame.

To

accommodate

M-series

channels

1,10

and

18,

special

module

covers

(Cat.

No. 359)

must

be

installed

on

the

Cat.

No. 280

modules

used

in

these

channels

only.

1.3

Dolby

SR

Compatibility

Electrically,

the

Dolby

SR

process

is

very

different

from

A-type

noise

reduction.

Both

Dolby

A-type

NR

and

Dolby

SR

are

complementary

processes

that,

when

decoded

properly,

give

excellent

results.

Dolby

SR,

however,

goes

far

beyond

noise

reduction

systems

in

its

ability

to

improve

the

overall

quality

of

a

recording

or

transmission

channel.

Dolby

A-type

and

Dolby

SR

are

not

considered

cross-

compatible--Dolby

SR

encoded

tapes

should

not

be decoded

with

Dolby

A-type

cards

and

vice

versa.

1.4

Dolby

SR

Calibration

As

with

A-type

noise

reduction,

Dolby

SR

requires

the

decode

module

to be

correctly

set

in

level

with

respect

to

the

encode

module.

With

A-type,

this

is

accomplished

using

Dolby Tone;

with

the

Dolby

SR

process,

it

is

achieved

using

a

new,

easily

identifiable

alignment

signal:

Dolby

Noise.

Dolby

Noise,

abbreviated

DN,

is

always

used

to

establish

correct

decode

level.

1-2

In

addition

to

the

Dolby

spectral

recording

circuits

and

the

Dolby

Noise

generator,

the

Cat.

No. 280

contains

an

important

new

feature--Auto

Compare.

The

Auto

Compare

circuit,

using

Dolby Noise

as

a

signal,

gives

the

user

valuable

gain

and

frequency

response

information

about

the

recording

channel.

The

Auto

Compare

mode

allows

an

automatic

aural

comparison

of

the

recorded Dolby

Noise

signal

and

the

internally

generated

pink

noise.

The

user

can

quickly,

by

ear,

verify

the

performance

of

the

recording

system

by

comparing

the

reference

pink

noise

with

the

Dolby Noise from

the

tape.

The

Auto

Compare

feature

is

discussed

fully

in

Section

3

--

Calibration.

1.5

Cat.

No. 280

Applications

The

following

is

a

summary

of

how

the

Cat.

No. 280

can

be

used

in

specific Dolby

interface

frames.

A

full

discussion

of

Cat.

No. 280

operation

in

these

units

is

covered

in

Section

5

--

Practical

Operation.

360

Series

Model

360

The

Model

360

is

intended

for

single-channel,

dedicated

encode

or

decode

operation.

Two

interface

frames

and

two

Cat.

No.

280

modules

are

required

for

one

channel

of

simultaneous

record

and

playback

operation.

The

Auto

Compare

feature

can

be

fully

operational

during

both

record

and

playback.

Model 361

The

Model

361

is

designed

for

changeover

operation

of

a

single

module

for

both

record

and

playback.

The

Cat.

No. 280

module

is

switched

into

the

record

and

playback

signal

paths

just

as

with

the

Cat.

No. 22.

The

Auto

Compare

sequence

is

available

only

when

playing

back

previously

recorded

Dolby Noise.

Model

362

The

Model

362

is

designed

to

hold

two

Cat.

No. 22

A-type

modules,

and

functions

as

a

dual-channel

Model 360.

Due

to

height

restrictions,

two

standard

Cat.

No. 280

modules

cannot

be

installed.

To

incorporate

Dolby

SR

in

the

Model

362,

a

special

adaptation,

the

Cat.

No. 280-L,

must

be

used.

The

Cat.

No. 280-L

contains

the

two

circuit

cards

that

make

up

the

standard

Cat.

No. 280

module,

with

one

mounted

behind

the

other.

This

results

in

a

module

that

is

of

single

thickness

but

double

length,

therefore

extending

forward

of

the

front

panel

by

7t

inches

(190

mm).

M-Series

The

M-Series

chassis

was

designed

to

hold

16

Cat.

No. 22

A-type

modules.

Two

chassis

can

be

linked

to

accommodate

24

or

32

channels.

It

is

possible

to

use

Dolby

SR

in

all

channels,

provided

that

special

covers

are

installed

on

the

Cat.

No. 280

modules

used

in

channels

1, 10

and,

in

the

M-24

unit,

channel

18.

Cat.

No. 280

modules

with

standard

covers

can

be

used

in

all

other

M-series

channels.

The

special

cover,

referred

to

as

the

Cat.

No. 359, will be

available

through

Dolby

product

distributors.

SP/XP

Series

The

greater

thickness

of

the

Cat.

No. 280

prohibits

its

use

in

the

SP

Series.

Additionally,

there

are

some

electrical

incompatibilities

with

the

Cat.

No. 230

carrier

card.

The

Cat.

No. 431,

due

in

late

1986,

will

fit

both

the

SP

and

XP

multi-track

units.

This

module

will be a

plug-in

replacement

for

the

entire

Cat.

No. 230/22

combination

in

existing

SP

units

and

for

the

Cat.

No. 331 A-type

module

in

the

newer

XP

frames.

Cinema

Products

(CP50,

CPI00,

CP200)

The

Cat.

No. 280

requires

minor

modification

for

use

within

cinema

units.

In

a few

special

situations,

however,

it

may

be

necessary

to

use

a

Cat.

No. 280

in

a

CP50,

CP100

or

a CP200.

In

this

case,

contact

Dolby

Laboratories

for

more

information.

2.1

General

Installation

2-1

SECTION

2

CAT.

NO.

280

INSTALLATION

If

the

Dolby

interface

frame

has

been

previously

aligned

for use

with

the

Cat.

No. 22 A-type module,

the

system

is

basically

ready

for use.

Installation

is,

therefore,

simply

a

matter

of

removing

the

existing

Cat.

No. 22 from

the

Dolby

interface

frame,

setting

the

configuration

switch

on

the

Cat.

No. 280,

and

plugging

in

the

module.

For

optimum

performance

of

the

Dolby SR circuits, however,

calibration

of

the

recording

system

and

interface

frame

input

and

output

levels

is

recommended

and

is

covered

in

Section 4.

If

the

interface

frame

(360

Series

or

M Series)

is

being

installed

at

the

same

time,

refer

to

the

appropriate

interface

frame

manual

for

information

regarding

connections, etc.

The

Cat.

No. 280

module

consumes

roughly

the

same

amount

of

power

as

the

Cat.

No. 22 A-type

module

and,

therefore,

has

the

same

cooling

requirements.

It

is

important

that

adequate

free

air

be provided

around

the

Dolby

interface

frame,

particularly

the

M-Series

unit,

which

should

always

have

a

blank

panel

above

and

below

the

chassis.

2.2

Configuration

Switch

and

Indicators

Before

installing

the

Cat.

No. 280,

the

user

should

be

familiar

with

the

basic

function

of

the

switches

and

indicators

mounted

on

the

module.

There

are

three

indicators

and

one

switch

on

the

Cat.

No. 280.

The

configuration

switch

should

be

set

for

the

appropriate

usage

condition.

• • • Set

s~itCh

to

360

M

361

usage

mode

On 0 II-i

SR

DOLBY

SPECTRAL

RECORDING

Cat.

No.

280

U 0

1.17

Dolby

laboratories

Inc.

San

francIsco

and

London

~~--~~~---,--~------~~--------~--------~---------~---~~-~~~-

D(] D lb ·

SR

DOLBY

SPECTRAL

RECORDING

o

ry

Cat. No.

280

Module

GREEN

Dolby Laboratories SR 280 Bedienungsanleitung

Beliebte Steuereinheit Handbücher anderer Marken