Teac Tascam Series Bedienungsanleitung

Andere Handbücher für Tascam Series

1

Dieses Handbuch passt für folgende Modelle

1

Inhaltsverzeichnis

Andere Teac Musikmixer Handbücher

Teac

Teac Tascam Portastudio 424 MkIII Bedienungsanleitung

Teac

Teac Tascam Series 15 Bedienungsanleitung

Teac

Teac 3 Bedienungsanleitung

Beliebte Musikmixer Handbücher anderer Marken

Neve

Neve 8816 Bedienungsanleitung

Mackie

Mackie Onyx Analogue Mixer Bedienungsanleitung

Behringer

Behringer EUROPOWER PMP518M Bedienungsanleitung

Peavey

Peavey S-32 Sanctuary Series Bedienungsanleitung

Rane

Rane MP 4 Bedienungsanleitung

True

True T9 Touchscreen Console Bedienungsanleitung

Studiomaster

Studiomaster Air Pro 24 Bedienungsanleitung

Pioneer

Pioneer SVM 1000 - Audio/Video Mixer Bedienungsanleitung

Roland

Roland M-160 Bedienungsanleitung

Yamaha

Yamaha MR1642 Bedienungsanleitung

Ecler

Ecler MAC40v Bedienungsanleitung

Pioneer

Pioneer DJM 909 - Battle Mixer W/Effects Bedienungsanleitung

Veeder-Root

Veeder-Root TLS-350 Series Bedienungsanleitung

Alto

Alto APM80.QUAD Bedienungsanleitung

Omnitronic

Omnitronic PM-211 Bedienungsanleitung

SoundCraft

SoundCraft B400 Bedienungsanleitung

Roland

Roland SoundCanvas SC-8820 Bedienungsanleitung

CARVIN

CARVIN RX 1200 Bedienungsanleitung

INSTRUCTION

MANUAL

TEAC

Tascam

Series

MODEL

15

AUDIO

MIXER

CONTENTS

1,

INTRODUCTION

TO

THE-MODEL

15

.....

1

2,

IMPEDANCE

MATCHING

—OR,

WHAT

PLUGS

INTO

WHAT

........

2

Mathematical

Formulas

. .

QuickTest

for

Safe

Loads

without

using

Test

Gear.

4

3.

THE

MODEL

16

FROM

MIC

IN

TO

LINE

OUTS

3.1

INPUT

MODULE

Mic

In

XLR’

Connectors

Mic:

ATT

‘Switch

Line

In

Jacks

Input

Select

Switch

SIGUE

Ss

ascites

Overload

L.E.D.

Accessory

Send/Receive

Jacks

Equalization

Controls

7

Aux

1

and

Aux

2

Pre-/Post-Fader

Function

..

.

Input

Fader

2...

,.

Direct

Out

Jack

SOLO

ta

toss

eis

NYNDOGMOGDGAAR

AA

MURS,

Fos.

SEM

Case

ween

Te

3.2

BUSS

MASTER

MODULE

Buss

tn

Jacks

.........

Buss

Fri;

cag

oie

st

ss.

2

Accessory

Send/Receive

Jacks

ee

Buss

Master

Fader

.

Tape

as

source

Buss

as

source

......

Monitor

Pan

Aux

3

and

Aux

4.

Echo

Receive

Section

COMDDMOMO

3.3

AUX

A

MASTER

MODULE

(CUE}

Aux

A

Mix

Control

..

2.0...

Aux

3

and

Aux

4

Push

Switchs

.

Echo

RCV

Rotary

Control

Master

Aux

A

Master

Fader

Aux

A

Module

Back

Panel

Aux

3

output

jacks

Aux

A

output

jacks

.

ae

Line

out

1~

4

(buss

master

outputs)

.

Sieh

fey'e

AO!

3.4

AUX

B

MASTER

MODULE

(ECHO)

Aux

B

Mix

Control

.....

Aux

3

and

Aux

4

Push

Switch

Aux

B

Master

Fader

Aux

B

Module

Back

Panel

Aux

4

output

jacks

Aux

B

output

jacks

. .

al

eaeteae

Line

out

§

~

8

{buss

master

outputs)

Bh

eS

11

Loading

Advice

....

3.5

CONTROL

ROOM

MONITOR

MODULE

Monitor

A

Output

Jacks

22...

JT

CR

MON,

Land

R

Output

Jacks

21

Push

Switches:

80.

ese

eevee

ti

Control

Room

Master

......-...-..0-

il

Solo:

Masteh

cos

Aadis

Beek

cw

Fisk

pshes

pai

Solo

L.ED.

ett

Auxiliary

Line

tn

Jacks

11

3.6

STUDIO

MONITOR

MODULE

Studio

Studio

MON

L-R

Outputs

Monitor

B

L-R

Outputs

3.7

TALKBACK

MODULE

Oscillator

Frequency

Select

Switch

Oscillator

Function

Select

Switch

Talkback

Microphone

..........

Studio

Aux

A

Slate

:

Headphone

Select

Switch

vod

3.8

POWER

SUPPLY

UNIT

Meter

Bridge

Connector

......

ib

ated

esavol

4.

STANDARD

PATCHES

.........

hobtidicine

.12

Recommended

8

Track

Setup

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

18

16

Track

Remix

Patch

with

an

Unorthodox

Stereo

Echo

........-

14

Recommended

16

Track

Setup

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

15

5.

LEVEL

SETTING

AND

OPERATION

CHECK

Line

in

—»

Access

send

........

wean

VE

Line

in

—>

Direct

out

of...

.

0...

cee

7

Line

in

—>

Line

out/Aux

out

...........

7

Check

and

adjustment

of

the

input

module

QverlQa

LED

0

2

055

(oa)

he

ba

arate

ated

we

18

Aux

1

—»

Aux

Asend

..........

1.19

Aux

2

—>

Aux

B

send

Line

in.

—>

Line

—>

Aux

3

—>

Aux

A

send

. .

20

Aux

3

—+AuxBsend

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

24

Line

in

—+

Line

out

—>

Aux

4

—+

Aux

B

send,

21

Aux

4

->

Aux A

send

Line

out

—>

Mon

A

left/right

Solo

circuit

Control

room

monitor

circuit

Studio

monitor

circuit

. ‘

Echo

RCV

circuit

......-.....

Meter

calibration

and

LED

circuit

Test

tone

oscillator

Talkback

circuit

......

Tape

in

circuit

...

Mic

input

(Model

301

Input

Module)

Phantom

power

supply

.............+4-

6.

EXPLODED

VIEWS

AND

PARTS

LIST

Model

15

Main

Frame

Model

301.

Input

Module

F

Model

302

Buss

Master

Module

Model

3034

Aux A

Module

Model

303B

Aux

B

Module

Model

304

Talkback

Module

Model

305A

Control

Room

Monitor

Module

.

Model

350B

Studio

Monitor

Module

Model

306

Power

Supply

Module

Model

307

Filler

Module

Tei

cae

Boats

Model

PS-15

Power

Supply

Unit

..........

7,

PC

CARDS

AND

PARTS

LIST

Input

Amplifier

PCB

Buss

Master

Amplifier

PCB

Aux

A

Amplifier

PCB

Aux

B

Amplifier

PCB

Talkback

Amplifier

PCB

Controt

Room

Monitor

Amplifier

PCB

.

2...

.

81

Studio

Monitor

Amptifier

PCB

He

satin

Bea

BT:

Power

supply

PCB.

.....

La

leah

genta

ieee

91

Mother

board:

PCB?

.ssasasries

cet

eed

das

95

8.

ELECTRONICS

SCHEMATICS

Block

diagram

........

Boe

aed

tad

hee

97

Modet

301

Input

Module

.....

Lashegarea

OS

Model

302

Buss

Master

Module

.

.

Se

4

OD.

Model

302A

Aux

A

Module

Model

303B

Aux

B

Module

Mode!

304

Talkback

Module

.

Model

305A

Control

Roam

Monitor

Module...

103

Model

305B

Studio

Monitor

Module

Model

306

Power

Supply

Module

Meter

bridge

..........

aerate

eves

Model

PS-15

Power

Supply

Unit

.....

9,

SPECIFICATIONS

109

1.

INTRODUCTION

TO

THE

MODEL

15

The

Madel

15

is

an

audio

mixing

console

designed

to

satisfy

the

requirements

of

modern

multichannel

re-

cording.

Many

of

the

auxiliary

mixing

systems

needed

are

built

in

and

canbe

re-routed

to

do

more

than

one

job.

Fast,

convenient

and

complete

operation

with

8

track

or

16

track

recorders

can

usually

be

accomplished

without

ré-patching.

However,

the

process

of

multi-

channel

recording

is

constantly

changing,

growing

more

complex

as

an

art

with

each

advance

in

technology.

Your

signal

processing

needs

may

require

a

unique

arrange-

ment

of

subsystems.

No

console

has

ever

been

built

so

large

and

complete

in

its

routing

that

it

could

solve

every

imaginable

problem

with

one

button.

Someone

will

al-

ways

be

able

to

come

up

with

that

unusual

situation

re-

quiring

“just

one

more

mix".

In

order

to

cope

with

these

unpredictable

requirements,

patch

points

are

provided

throughout

all

signal

pathways

on

the

M-15.

As

our

mixing

console

becomes

more

flexible,

the

amount

of

time

needed

to

understand

the

available

func-

tion

increases

as

well.

The

main

signal

path

from

mic

in

to

line

out

is

still

fairly

straight

forward.

The

require-

ments

have

not

changed

much

since

the

days

of

“mono”

but

the

routing

for

echo

sends,

multiple

source

cue

feeds,

and

stereo

monitoring

can

be

hard

to

visualize.

The

be-

ginner

often

overlooks

the

significance

of

connections

that

would

be

immediately

obvious

to

the

experienced

recording

engineer.

If

you

expect

to

find

that

“extra

mix”

quickly,

you

must

be

prepared

to

study

the

layout

of

the

M-15

thoroughly.

In

most

instances

the

physical

arrangement

of

the

controls

on

the

top

pane!

has

very

little

to

do

with

the

sequence

of

electronic

parts

inside,

The

actual

wiring

order

is

the

information

you

need

to

understand

to

use

the

M-15

successfully.

As

an

example,

if

the

controls

on

an

input

module

actually

followed

the

order

in

which

they

are

wired,

the

module

top

panel

would

look

like

this.

We'll

put

the

jacks

on

the

top,

as

well

as

the

switches

and

faders.

While

this

arrangement

of

controls

might

help

the

beginner

to

understand

the

flow

of

signal

in

the

module,

it

would

be

very

inconvenient

to

operate.

Still,

the

wiring

sequence

must

be

understood

before

the

more

complex

functions

of

the

M-15

can

be

used

successfully,

so

along

with

the

documentation

you

will

need

for

service

{sche-

matic

diagrams,

mother

board

layouts

and

mechanical

disassembly

information)

we

include

a

simplified

electri-

cal

sequence

chart

called

a

BLOCK

DIAGRAN.

This

drawing

shows

all

the

controls,

switches,

amplifying

stages

and

connectors

in

their

proper

order.

Learning

to

read

it

will

provide

the

answers

to

any

questions

about

what

comes

where

on

the

inside.

Even

though

the

block

diagram

can

indicate

what

is

available

in

the

way

of

ex-

tra

circuit

flexibility,

it

can’t

explain

why

2

connection

or

switch

has

been

included,

or

suggest

a

standard

layout.

In

the

following

sections

of

this

manual

we

will

do

our

best

to

describe

the

individual

functions

and

controls

of

the

M-15

and

how

they

can

be

arranged

in

more

than

one

sequence,

but

your

mixing

needs

may

be

best

served

by

an

arrangement

of

inputs

and

sub-system

connections

you

work

out

for

yourself.

Good

luck

with

your

sound.

‘EDs

2fB«

>>

<0:

fy

ea

2.

IMPEDANCE

MATCHING

—

OR;

WHAT

PLUGS

INTO

WHAT

All

electronic

parts

including

cabies

and

non

powered

devices

(mics,

passive

mixers

and

such)

have

impedance,

measurable

in

ohms

{symbol

$2

or

Z).

Impedance

is

the

total

opposition

a

part

presents

to

the

flow

of

signal,

and

it's

important

to

understand

some

things

about

this

value

when

you

are.making

connections

in

your

mixing

system.

The

outputs

of

circuits

have

an

impedance

rating

and

so

do

inputs.

What’s

good

?

What

values

are

best?

It

depends

on

the

direction

of

signal

flow,

and

in

theory,

it

looks

like

this:

plug

into

OUTPUTS

OUTPUTS

It

is

generally

said

that

the

output

impedance

(Z)

should

be

as

low

as

possible.

100

ohms,

10

ohms,

the

lower,

the

better

in

theory.

A

circuit

with

a

low

output

impedance

will

offer

a

low

resistance

to

the

passage

of

signal,

and

thus

will

be

able

to

supply

many

multipte

connections

without

a

loss

in

performance

or

a

voltage

drop

in

any

part

of

the

total

signal

pathway.

Low

impedance

values

can

be

achieved

economically

by

using

transistors

and

integrated

circuits

but

other

considera-

tions

are

still

a

problem

in

practice.

1,

The

practical

power

supply

is

not

infinitely

large.

At

some

point

even

if

the

circuit

is

capable

of

supplying

more

energy,

you

will

run

out

of

“juice”.

2.

Long

before

this

happens,

you

may

burn

out

other

parts

of

the

circuit.

The

output

impedance

may

be

close

to

the

theoretically

ideal

“O

ohms”

but

many

parts

in

the

practical

circuit

are

not.

Passing

energy

through

a

resistance

generates

heat,

and

too

much

current

will

literally

burn

parts

right

off

the

circuit

card

if

steps

are

not

taken

to

prevent

catastrophic

failure.

3.

Even

if

the

circuit

does

not

destroy

itself,

too

high

a

demand

may

seriously

affect

the

quatity

of

the

audio.

Distortion

will

rise,

frequency

response

will

suffer,

and

you

will

get

poor

results,

++

INPUTS

INPUTS

Inputs

should

have

very

high

impedance

numbers,

as

high

as

possible,

100,000

ohms,

1

million

ohms,

more,

if

it

can

be

arranged.

A

high

resistance

to

the

flow

of

signal

at

first

sounds

bad,

but

you

are

not

going

to

build

the

gear.

if

the

designer

telis

you

his

input

will

work

proper+

ly

and

has

no

need

for

a

large

amount

of

signal,

you

can

assume

that

he

means

what

he

says.

For

you,

a

high

input

impedance

is

an

unalloyed

virtue.

It

means

that

the

circuit

will

do

its

job

with

a

minimum

of

electrical

energy

as

a

beginning.

The

most

“economical”

electronic

devices

in

use

today

have

input

impedances

of

many

millions

of

ohms,

Test

gear.

For

example,

voltmeters

of

good

quality

must

not

draw

signal

away

from what

they

are

measuring

or

they

will

disturb

the

proper

operation

of

the

circuit.

A

design

engineer

needs

to

see

what

is

going

on

in

his

design

without

destroying

it,

so

he

must

have

an

“efficient”

device

to’

measure

with.

The

classic

measurement

for

Output

impedance

is

to

load

a

circuit

until

the

voltage

drops

6

dB

(to

half

the

original

power)

and

note

what

the

load

value

is.

In

theory,

you

now

have

a

load

impedance

that

is

the

same

as

the

output

impedance,

If

you

reduce

the

load

gradually,

the

dB

reading

will

return

slowly.

to

its

original

value.

How

much

drop

is

acceptable?

What

load

will

be

left

when

an

acceptable

drop

is

read

on

the

meter?

When

the

load

value

is

approximately

seven

times

the

output

impedance,

the

needle

is

still

a

little

more

than

1dB

lower

than

the

origina!

reading.

Most

technicians

says.”

1

dB,

not

bad,

that’s

accept-

able.”

We

at

TEAC

must

say

we

do

not

agree.

We

think

that

a

seven

to

one

ratio

of

input

(7)

to

output

(1)

is

not

a

high

enough

ratio

and

here’s

why.

1.

The

measurement

is

usually

made

at

a

midrange

fre-

quency

and

does

not

show

true

loss

at

the

frequency

extremes,

What

about

drop

at

20

Hz?

2.-All

outputs

are

not

measured

at

the

same

time.

Most

people

don't

have

twenty

meters,

we

do.

Remember,

everybody

plays

together

when

you

record

and

the

circuit

demands

in

practice

are

simultaneous,

All

draw

power

at

the

same

time.

Because

of

the

widely

misunderstood

rule

of

thumb,.

the

seven

to

one

ratio,

we

will

give

you

the

values

for

outputs

in

a

complete

form.

Even

though

the

true

output

impedance

is:

Line

Out/Aux

Out

100

ohms

CR

Mon

Out

100

ohms

a

Studio

Mon

Out 100

ohms

Aux

A

and

Aux

B

Out

100

ohms

Mon

A

and

Mon

B

Out

100

ohms

'

Aux.

3

and

Aux

4

Out

400

ohms

Tape

Foldback

Equal

to

tape

recorder

output

im-

pedance

connected

to

TAPE

IN.

Direct

Out 100

ohms

Access

Send

100

ohms

Talkback

Out

Less

than

1

ohms

Headphone

Out

Less

than

1

ohrns

For

the

practical

reasons

explained

previously,

we

feel

that

7

:1

ratio

is

not

sufficient.

To

use

this

rule

of

thumb,

you

must

use

this

higher

value.

We'll

call

this

value

the

“output

load

impedance.”

Line

Out/Aux

Out

1.4k

ohms

CR

Mon

Out

1.4k

ohms

Studio

Mon

Out

1.4k

ohms

Aux

A

and

Aux

B

Out

1.4k

ohms

Mon

A

and

Mon

B

Out

1.4k

ohms

Aux

3

and

Aux

4

Out

1.4k

ohms

Tape

Foldback

Equal

to

tape

recorder

output

im-

pedance

connected

to

TAPE

IN.

Direct

Out

1.4k

ohms

Access

Send

1.4k

ohms

This

is

a

number

that

will

give

good

results

with

the

7:1

method.

To

go

one

step

further,

here

are

the

actual

minimum

ohmic

values

we

feel

are

wise.

Connect

no

total

input

impedance

load

higher

than:

Line

Out/Aux

Out

10k

ohms

CR

Mon

Out

10k

ohms

Studio

Mon

Out

10k

ohms

Aux

A

and

Aux

B

Out

10k

ohms

Mon

A

and

Mon

B

Out

10k

ohms

Aux

3

and

Aux

4

Out

10k

ohms

Tape

Foldback

Equat

to

tape

recorder

output

im-

pedance

connected

to

TAPE

IN.

Direct

Out 10k

ohms.

Access

Send

10k

ohms

Input

impedance

is

more

straight

forward

and

re-

quires

only

one

number.

Load

is

load,

and

here

are

the

values

for

the

Modal

15:

Mic

Input

20k

ohms

Line

Input

50k

ohms

Echo

Receive

20k

ohms

Tape

Input

40k

ohms

Buss

Input

20k

ohms

Access

Receive,

input

module

50k

ohms

Buss

Master

module

10k

ohms

Line

1,

2,

3

Mon

100kohms

if

one

output

is

to

be

“Y”

connected

to

two

inputs,

the

total

impedance

of

the

two

inputs

must

not

exceed

the

toad

impedance,

as

mentioned

before,

and

if

it

be-

comes

necessary

to

increase

the

number

of

inputs

with

slight

exceeding

of

the

load

spec.,

you

must

check

for

drop

in

level,

loss

of

headroom,

low

frequency

response,

or

else

suffer

a

loss

in

quality,

{f

one

input

is

10,000

ohms,

another

of

the

same

10,000

ohms

will

give

you

a

total

input

impedance

(load)

of

5,000

ohms.

To

avoid

calculations

you

can

do

this

when

you

have

two

identi-

cal

inputs

to

connect

to

one

output.

Take

the

lower

value

of

the

two

input

impedances

and

divide

it

in

half.

If

the

number

you

have

is

still

7

times

the

output

impedance,

you

can

connect

both

at

the

same

time.

When

you

have

more

than

two

loads

(inputs),

just

dividing

the

lowest

impedance

by

the

number

of

inputs

will

not

be

accurate

unless

they

are

all

the

same

size

but

if

you

still

get

a

safe

load

(higher

than

7

:

1

ratio)

by

this

method,

you

can

connect

without

worry.

MATHEMATICAL

FORMULAS

If

you

must

have

exact

values,

here

are

the

formulae:

1

For

more

than

2

—-

Rx=

ab

eg

te

ote

Ri

R2

RB

Rn

Rx

=

value

of

total

load

For

2

loads

‘or

inputs

—

Rx=

nine

Ri

+

R2

Finding

Impedance

Values

on

Other

Brands

of

Equipment.

When

you

are

reading

an

output

impedance

specifi-

cation,

you

will

occasionally

see

this

kind

of

statement:

Minimum

load

impedance

=

X

ohms

or

Maximum

load

impedance

=

X

ohms

These

two

statements

are

trying

to

say

the

same

thing,

and

can

be

very

confusing.

The

minimum

load

impedance

says,

please

don't

make

the

number

of

ohms

you

connect

to

this

output

any

lower

than

X

ohms.

That‘s

the

lowest

number.

The

second

statement

changes

the

logic,

but

says

the

exact

same

thing.

Maximum

load

impedance

refers

to

the

idea

of

the

load

instead

of

the

number,

and

says,

please,

don’t

make

the

toad

any

heavier.

How

do

you

increase

the

load?

Make

the

number

lower

for

ohms.

Maximum

load

=

minimum

ohms,

so

read

carefully.

When

the

minimum/maximum

statement

is

made

you

can

safely

assume

that

the

manufacturer

has

already

done

the

“saven

times

is

best”

ratio

calculation,

And

the

number

given

in

ohms

does

not

have

to

be

multiplied.

You

can

match

the

ohmic

value

of

your

input

to

this

number

of

ohms

successfully,

but

as

always,

higher

ohms

will

be

okay

(Less

load).

7

QUICK

TEST

FOR

SAFE

LOADS

WITHOUT

USING

TEST

GEAR

tf

you

don‘t

know

the

exact

value

input

impedance

for

a

device

you

want

to

connect

there

are

still

a

couple

of

ways

to

test

it.

1,

Listen

to

the

main

signal

output

{line

out

or

Aux

out)

as

you

remove

and

re-connect

the

device

to

the

direct

out.

If

you

hear

a

drop

in

level

or

a

change

in

the.tonal

balance

of

the

sound

on

the

main

line

out,

the

device

is

likely

to

be

drawing

too

much

current

and

is

unsuitable.

lf

you

can

get

a

steady

tone

to

work

with,

you

can

read

your

VU

meter

and

make

this

measurement.

Patch

the

steady

tone

through

the

mixer

from

input

to

line

out.

Set

the

faders

so

the

tone

reads

“O"

VU

‘on

the

meter.

Now

connect

the

device

you

wish

to

check

to

the

“direct

out”

on

the

input

module

you

are

using

for

the

steady

tone,

If

the

drop

in

level

on

the

meter

is

more

than

0.5

dB,

the

device

has

too

low

a

value

of

input

impedance.

It

will

not

damage

the

mixer

to

use

it,

but

it

will

affect

the

quality

of

the

signal

on

the

main

line.

Nn

If

making

the

connection

to

the

direct

out

causes

the

main

line

signal

to

drop

6dB,

the

input

impedance

of

the

device

is

the

same

as

the

true

output

impedance.

You

should

also

know

that

to

make

the

“disconnect,

re-connect

the

load”

test

in.

section

1

above,

you

must

actually

pull

out

the

connection.

Many

devices

will

affect

a

circuit

when

the

signal

cable

is

connected,

even

if

they

are

not

plugged

in

the

power

line,

or

their

power

(AC)

switch

is

in

the

off

position.

3.

THE

MODEL

15

FROM

MIC

IN

TO

LINE

OUTS

In

our

description

of

the

seven

different

types

of

module

used

in

the

M-15,

we'll

disregard

the

physical

layout

and

follow

the

block

diagram,

or

actual

wiring

sequence.

3.1

INPUT

MODULE

All

sixteen

input

modules

are

identical

and

can

be

interchanged

without

modification.

An

additional

8

modules

can

be

added

io

the

frame

at

any

time.

The

extra

positions

are

completely

wired,

with

one

excep-

tion.

The

RMX

(remix)

position

will

be

inoperative

on

the

last

8

positions

(17-24)

because

there

is

no

provi-

sion

on

the

tape

A

or

B

circuit

for

the

extra

8

busses

necessary.

All

other

features

will

be

identical

in

the

24

input

mode.

MIC

IN

XLR

CONNECTOR

This

connector

and

the

small

amount

of

wiring

immediately

in

front

of

the

input

transformer

are

the

oniy

parts

of

the

M-15

that

use

the

3

wire

balanced

type

of

circuit.

The

Mic

in

XLR,

the

pad

of

20 dB

that

is

switch

selectable

and

the

transformer

primary

are

“balanced”.

All

circuits

thereafter

are

2

wire

“single

ended”,

one

hot

lead,

one

ground.

MIC

ATT

SWITCH

When

this

switch

is

set

to

the

left,

a

balanced

pad

lowers

the

“Mic

In"

level

by

20

dB,

Since

the

maxirnum

permissible

input

to

the

transformer

is

0

dB

(1

volt),

when

high

output

mic’s

are

used

on

very

loud

sounds,

extra

external

pads

may

be

required

to

lower

the

input

signal

to

safe

levels.

The

input

load

impedance

of

the

“Mic

In”

group

of

parts

is

20

kohms.

This

circuit

cor-

rectly

matches

50-250

ohm

low

impedance

microphones.

LINE

IN

JACK

An

RCA

jack

on

the

rear

of

each

input

module.

The

maximum

signal

you

can

apply

here

is

+28

dB

(25

volt).

The

Mic

Att

switch

does

not

affect

this

input.

The

input

impedance

is

50

kohms.

INPUT

SELECT

SWITCH

This

switch

has

3

positions,

left

selects

the

Mic

in

XLR,

center

selects

the

Line

In

RCA

jack

on

the

back

of

the

module,

and

right,

marked

“w”

(remix),

selects

as

an

input

one

of

the

“Tape

In”

jacks

on

the

buss

master

modules.

Since

each

input

module

will

receive

only

one

“Tape

In”

signal,

we'll

provide

a

chart

to

show

which

signal

goes

to

which

module.

The

“Tape

In”

A

and

B

systems

normally

feed

the

monitor

sections

on

the

buss

master

modules.

The

“s#”

{remix}

position

on

the

input

module

will

allow

you

to

route

tape

playback

signa!

to

the

input

module

for

final

mixing

without

moving

the

cabies

plugged

in

at

tape

A

or

B

to

the

input

“Line

In”

jacks,

in

addition,

selecting

this

“m”

(remix)

position

on

the

input

module

will

not

disable

the

normal

operation

of

the

monitor.

TAPE

A

JACK,

UPPER

ROW

©:

ej

H

Oi"

Gr?

OF

on

10

TAPE

8

JACK,

LOWER

ROW

Signal

will

go

to

both

circuits

at

the

same

time,

allowing

separate

use

of

the

monitor

A

and

B

outputs

as

extra

mixes.

True

stereo

echo

is

an

obvious

first

choice,

and

the

mixdown

machine

can

be

monitored

using

a

“Line

In”

position

on

the

control

room

monitor

module.

Since

the

remix

position

can

be

selected

one

module

at

a

time,

a

single

track

may

be

equalized

and

monitored

without

disturbing

“Mic

{n”

settings

on

the

whale

mix,

A

deci-

sion

can

be

made

quickly

on

the

artistic

success

or

failure

of

an

individual

part

without

the

need

to

place

the

entire

console

in

remix

mode

just

to

see

the

effect

of

corrective

equalization

on

a

single

track.

If

you

examine

the

input

module

numbers

you

will

see

that

the

Number

One

module

is

the

one

closest

to

the

“Buss

Master

1

Module.”

The

mixing

console

is

numbered

from

right

to

left

on

the

input

module

section,

but

from

left

to

right

in

the

buss

master

section.

This

system

has

been

adopted

in

order

to

keep

the

mixing

console

as

compact

as

possible

in

16

input

configuration.

Expanding

to

24

inputs

will

now

add

modules

to

the

left

of

the

ones

already

installed,

and

the

numbering

will

rernain

correct,

even

though

inverted.

Since

the

TAPE

IN

jack

on

the

buss

master

module

actually

feeds

3

separate

mixing

positions

it

will

present

a

more

severe

load

to

anything

connected

to

it

than

“Line

in“

on

the

module.

TAPE

IN's

have

an

input

load

impedance

of

40kohms,

LINE

IN‘’s

(on

the

input

module}

have

an

input

impedance

of

50

kohms.

TRIM

This

control

witl

alter

the

gain

of

the

first

amplifier

in

the

console.

It

will

affect

the

fevel

of

any

signal,

Mic,

Line,

or

#.

With

this

pot

rotated

fully

clockwise

(right-

ward),

the

maximum

gain

of

the

first

amplifier

is

48

dB.

In

this

position,

the

maximum

input

signal

before

over-

load

is

-38

dB

(0.013V).

To

improve

the

performance

of

this

first

gain

critical

stage,

for

the

M-15,

TEAC

has

elected

to

build

a

discrete

amplifier

with

FET

inputs

instead

of

using

the

standard

|.C.’s

now

available.

Sub-

stantial

improvements

in

performance

have been

realized

as

a

result.

When

the

pot

is

in

its

minimum

setting

(fully

counterclockwise

or

leftwards)

the

gain

is

reduced

to

8

dB

and

the

maximum

signal

that

can

be

handled

with-

out

overload

wil]

be

+2

dB

(1.3V}.

Remember,

these

overload

figures

refer

to

the

input

of

the

amplifier,

not

the

input

plug

or

connector,

Losses

occur,

and

pads

can

be

inserted

before

this

point.

The

maximum

signal

that

can

be

applied:

to

the

line

in

jack

is

+28

dB

(25V)

with

the

Trim

rotated

fully

leftwards,

and

-12

dB

(0.25

mV)

with

the

Trim

rotated

fully

rightwards.

OVERLOAD

L,E.D.

When

signals

high

enough

to

make

the

ACCESS

SEND

jack

output

exceed

+15dB

are

applied

to

the

INPUT

module,

this

L.E.D.

will

light

up.

Trim,

or

the

Mic

Att

pad

should

be

adjusted

until

the

L.E.D.

remains

out

when

signal

is

present.

When

recording

extremely

percussive

transient

material,

it

may

require

full

negative

trim

and

pad

to

prevent

this

L.E.D.

from

flickering

on

strong

peaks.

Changing

to

a

less

sensitive

mic

may

help.

On

the

Aux

B

Master

Module

you

will

find

a

rotary

switch

marked

NORM/MIX.

This

control

will

alter

the

sensitivity

of

the

overload

signal

L.E.D.'s

on

the

input

modules

so

that

they

can

be

used

as

a

signal

indicating

system

or

tracer.

When

this

switch

is

set

to

“MIX”

the

sensitivity

of

the

L.£.D.

driver

is

increased

by

20dB.

The

L.E.D.

will

now

show

you

which

modules

have

signal

applied

to

their

inputs.

To

again

check

for

input

overload,

you

must

switch

this

control

back

to

"NORM."

It

affects

all

input

L.E.D.'s

simultaneously.

F

ACCESSORY

SEND

—

RECEIVE

JACKS

The

high gain

provided

by

the

use

of

discrete

cir-

cuitry

in

our

new

mic

preamplifier

allows

us

to

place

a

“patch-point”

in

this

more

useful

position.

The

level

at

the

send

jack

is-10

dB

(0.3V)

and

the

output

load

impe-

dance

is

1.4k

ohms.

A

limiter

connected

to

this

point

in

‘the

M-15

circuit

can

now

be

set

to

a

range

of

compression

that

will.

not

alter

when

either

the

equalizer

(the

next

stage)

is

adjusted

or

the

input

fader

is

moved

(the

stage

after

the

EQ

amps).

This

pair

of

jacks

is

not.“normalled”

so,

when

no

device

is

bridged

from

send

to

receive,

jumpers

must

be

in

place

for

signal

to

flow

to

the

EQ

amps

and

on

through

the

console,

However,

since

all

the

mixing

controls

lie

after

the

“

Receive”

jack,

it

is

possible

to

use

“Accessory

Receive”

as

an

input,

and

by-pass

the

the

first

gain

stage.

The

only

functions

that

will

be

lost

are

the

trim

and

overload

indicators.

The

signal

quality

will

improve

slightly

but

it

will

not

be

possible

to

switch

to

“Mic

In",

“Line

In”

or

“m”

without

re-patching.

This

unorthodox

patch

is

suggested

for

final

remix

when

all

recording

has

been

completed,-and

more

time

for

patch-

ing

is

available.

Maxirnum

level

in

will

be

+18

dB,

(8

volt)

input

impedance

is

50

kohms.

EQUALIZATION

CONTROLS

The

M-15

has

6

frequency,

4

control

E.0.

divided

into

two

sections

of

two

knobs

each.

On

the

upper

sec-

tion,

1OKHz

fixed,

3kHz

or

5k

Hz

switch

selectable.

On

the

lower

section,

200

Hz

or

800

Hz,

switch

selectable,

and

75.Hz,

fixed.

The

fixed

frequency

controls

will

not

work

unless

their

frequency

select

switch

is

away

from

the

center,

or

“EQ

OFF”

position.

Either

side

will

do

but

center

is

“OFF”

for

both

knobs

in

a

section.

The

chart

below

shows

the

range

for

each

frequency,

boost

and

cut.

DIRECT

OUT

6)

(101

©

soLo

AUX

1

AND AUX

2

PRE-/POST-FADER

FUNCTION

Both

of

these

Auxiliary

Mixing

Positions

can

be

fed

from.

more

than

one

point

in

the

signal

path..To

make

their

operation

clear

we’ll

use

a

section

of

the

Biock

Diagram

to

show

the

connections.

Since

there

is

no

switch,

the

direction

of

rotation

of

the

control

will

determine

which

point

signal

will

be

derived

from.

Counterclockwise

(leftwards)

rotation

of

either

the

Aux

1

or

Aux

2

control

will

draw.

signal

before

the

input

fader.

if

you

choose

this

source,

moving

the

input

fader

will

not

affect

the

level

of

your

Aux

Mix.

This

is

useful

for

making

up

cue

mixes

for

musicians.

Nothing

is

more

frustrating

to

a

player

than

having

the

drums

suddenly

disappear

from

the

earphone

mix

during

rehearsal.

Clock-

wise

(rightwards)

rotation

of

either

the

Aux

1

or

Aux

2

control

will

draw

signal

after

the

input

fader.

This

source

is

useful

for

echo

mixes.

As

the

input

fader

is

closed,

the

echo

send

will

also

be

reduced,

“fading

out”

will

not

leave

you

with

a

“ghost”

coming

from

your

echo

return.

Each

control

has

a

detent

you

can

feel

at

“center”

allowing

you

to

be

sure

it

is

completely

“OFF”

and

drawing

no

signal

from

either

side.

PRE,

PosT

Rotate

CCW

(left)

to

increase

Rotote

CW

(right)

to

increase

oN

ON

This

type

of

control

is

called

a'"W”

pot.

Its

use

in

the

M-15

allows

us

to

eliminate

a

switch

that

would

otherwise

be

necessary

to

select

“pre”

or

“post”.

Both

circuits

may

be

set

to

the

same

side

safely,

either

pre

or

post.

You

may

have

2

postfader

echo

sends

or

2

pre-

fader

cue

systems

or

one

of

each

as

the

needs

of

the

moment

require.

Because

of

slight

differences

in

func-

tion

on

the

master

control

of

each

circuit,

we

suggest

that

you

use

Aux

1

as

your

input

cue,

and

Aux

2

as

an

echo

circuit,

but

this

is

basically

a

recommendation

not

@

command.

The

reasons

will

become

more

clear

when

we

describe

the

final

controls

for

each

function.

(See

“Aux

A

Module”,

“Aux

B

Module”

Pages

9

and

10).

INPUT

FADER

Controls

the

signal

level

of

all

prior

stages.

Faders,

also

called

pots

or

attenuators

always

cause

loss

in

order

to

control

signal

level.

Gain

stages

in

an

electronic

device

always

run

“wide

open”

at

whatever

gain

they

are

set

for,

unless

they

have

provision

for

"Trim"

or

actual

gain

adjustment.

In

the

M-15

only

two

of

the

many

amplifiers

employed

actually

have

“Trim”,

the

first

gain

stage

or

Mic

Pre

and

the

Buss

Summing

amplifier.

When

you

advance

any

straight

line

fader

on

the

M-15

you

are

just

reducing

the

loss

it

causes.

The

entire

signal

flows

to

the

next

stage

only

if

the

fader

is

“wide

open”.

or

up

all

the

way.

DIRECT

OUT

JACK

There

is

no

special

control

for

this

output

on

the

top

panel.

It is

“Hot”

all

the

time,

and

provides

an

un-

mixed

single

signal

output

of

whatever

has

been

assigned

to

the

module.

This

direct

ouput

can

be

used

for

a

variety

of

purposes.

1,

A

subsidiary

mix

can

be

made

by

using

an

accessory

mixer

fed

by

this

output.

2.

One

mic,

one

track

recording

happens

frequently,

and

using

direct

out

will

by

pass

unneeded

summing

networks

and

amplifiers.

Going

“Direct”

to

the

re-

corder

will

result

in

a

cleaner

signal.

On

the

M-15

monitoring

wiil

be

possible

by

switch-

ing

the

appropriate

monitor

section

to

“

Tape”

and

listen-

ing

to

the

recorders

electronics

instead

of

a

buss

master,

For

metering,

either

the

recorder

or

an

accessory

meter

bridge

can

be

used,

(MB-20}

Since

the

amplifier

that

feeds

this

jack

also

feeds

the

buss

assign

network

and

the

post

fader

cue

systems,

it

is

wise

to

calculate

the

total

load

carefully.

The

output

load

impedance

of

this

jack

is

1.4k

ohms.

The

load

of

the

pre-wired

circuits

restrict

the

connection

of

this

output

to

a

single

circuit

at

a

time,

unless

the

equipment

you

plan

on

connecting

here

is

known

to

have

very

high

values

for

input

impedance

{100

kohms

or

more).

SOLO

Depressing

this

pushbutton

bypasses

whatever

source

you

have

selected

on

the

control

room

monitor

module

and

substitutes

the

signal

appearing

at

this

point

in

the

input

module.

More

than

one

module

at

a

time

may

be

selected

producing

a

“Mix”

on

this

buss.

Since

this

“Mix”

goes

only

to

the

monitor

module,

all

other

line

output

functions

remain

uninterrupted

and

recording

will

not

be

affected.

The

Solo

buttons

latch,

push

again

to

release.

Whenever

any

button

is

down,

an

L.E.D

lights

on

the

control

roorn

rnodule

to

remind

you

that

the

normal

selection

function

of

monitor

has

been

by-

passed.

The

Solo

signal

is

monophonic,

but

is

distributed

equally

between

both

monitor

outputs.

You

will

be

able

to

set

your

EQ,

but

echo

return

and

stereo

placement

will

be

disabled,

~

PAN

POT

AND

BUSS

ASSIGNMENT

Each

input

rodule

may

only

feed

signal

to

four

of

the

8

buss

master

modules

at

a

time.

A

fifth

push

switch

in

the

assignment

section

marked

Buss

In

1~

4

on

one

side

and

5

~

8

on

the

other

will

transfer

the

four

outputs

of

the

switch

section

from

one

group

(Up

-

1

~

4)

to

the

other

(Down

-

5

~

8)

Depressing

more

than

one

button

will

engage

the

“Pan"

control.

This

single

knob

works

two

faders

that

are

wired

“back

to

back”.

As

you

rotate

the

knob,

one

fader

is

turned

up

as

the

other

is

turned

down.

When

the

contro!

is

“dead

center”

each

fader

is

still

reducing

the

signal

slightly

so

that

the

signal

transition

through

“center”

does

not

become

louder

as

you

“Pan”

through

it.

When

both

speakers

in

a

stereo

pair

are

producing

sound,

you

don’t

need

as

much

power

to

maintain

a

con-

stant

volume.

tf

only

one

button

is

depressed,

the

pan

control

has

no

effect

on

the

signal.

When

any

two

buttons

are

depressed,

the

tower

number

is

“

Panned”

to

full

on-when

the

control

is

turned

as

far

as

it

will

go

counterclockwise,

the

higher

is

“Panned”

to

full

on

clockwise.

The

“Pan”

logic

for

3

or

4

button

arrays

is

easiest

to

explain

with

some

drawings.

If

shaded

buttons

are

as-

sumed

to

be

down,

the

logic

is:

me

CT

oS

Typical

examples

of

multichannel

panning

Since

the

entire

pan

logic

diagram

also

transfers

to

buss

group

5~

8,

panning

signal

‘to

busses

in

separate

groups

will

not

be

possible,

As

an

example

to

.“Pan”

between

Buss’1,

and

Buss

6,

or

between

Busses

4

&

5.

MUTE

The

mute

switch

is

a

program

interrupt,

and

will

affect

your

recording.

When

depressed,

it

disconnects

the

output.

of

the

module

from

the

Buss

assign

section

and

the

Direct

Out

Jack,

However,

the

Aux

1

and

2

cir-

cuits

are

not

affected.

Cue

or

echo

functions

will

not

be

interrupted.

If

it

is

necessary

to

mute

echo

as

well

while

remixing,

the

“input

select”

switch

will

disconnect

signal

at

the

beginning

of

the

chain

as

long

as

you

have

a

posi-

tion

available

that

has

no

signal

appearing

on

its

back

panel

connector.