Page 1

dbx
Model 400X
Program-Route
Instruction
Selector
Manual
Page 2

INSPECTION
Your
it.
Nevertheless,
of
damage.
material,
In
you
ever
In
contain a set
mounting
The
the
supplied
tion;
other
generate
CAUTION
NO USER-SERVICEABLE PARTS INSIDE.
REFER SERVICING TO
VICE PERSONNEL.
TO
TRIC SHOCK. DO
COVER (OR
and
INSTALLATION
unit
was
carefully
we
recommend
If
there
and
notify
any
case
need
to
addition
(two
brackets,
400X is
brackets.
components
excessive
REDUCE THE RISK OF ELEC-
is
such
your
it
is a
good
ship
your
to a model
pairs)
of
and a warranty
mountable
No
may
heat.
NOT
BACK)
QUALIFIED
dbx
REMOVE
packed
evidence,
dealer
idea
unit
in
400X
hookup
into
special
be
stacked
SER-
at
the
examining
don't
immediately.
to
save
the
the
future.
and
this
cables
with
/registration
any
standard
cooling
or
above
factory
both
carton
destroy
carton
instruction
conventional
card.
19-inch
ventilation
or
below
alert
uninsulated
within
may
constitute
to
alert
important
instructions
accompanying
in a
carton
and
the
carton
and
packing
manual,
(48.3-cm)
is
the
This
you
the
be
of
persons.
This
you
designed
contents
or
any
materials
the
RCA
equipment
required
400X
provided
symbol
of
the
dangerous
unit's
sufficient
a
risk
symbol
of
the
operating
in
the
the
to
for
of
the
carton
phono
in
any
is
intended
(pin)
presence
voltage
enclosure
magnitude
of
electric
is
intended
presence
and
literature
unit.
protect
any
signs
packing
should
should
plugs,
rack
with
installathey
don't
to
of
that
to
shock
to
of
maintenance
WARNING:
Rain
VOLTAGE
small
cover
which
Don't
For
"dbx"
is a registered
or
Moisture.
If
you
screwdriver.
plate,
exposes
turn
120V
ac:
10
120V--
To
Prevent
CONVERSION
ever
move
the
the
plate
AC
120V
AC
need
to
For
the
the
switch,
switch
over.
I
120V
~
trademark
Fire
or
change
US
turn
in
its
Shock
version
new
the
Hazard,
voltage
model,
the
plate
voltage
e]
~·220V
Use a
and
screwdriver
slide
of
dbx
Inc.,
Newton,
Do
Not
Expose
setting,
first
upside
position),
For
move
unscrew
down
220V
and
ac:
Important:
for
European
UL
listed
model.
o@~@o
Mass.
USA
(180°,
This
model
AC
This
the
the
screw
setting
120V
Appliance
switch
small
in
other
it
back
and
with
voltage
is
only
not
to
a
words,
on.
for
Page 3

CONTENTS
Front
Rear
Some
Usage
Block
Schema
Warranty
Important
panel
jacks (connections)
typical
notes
diagram
tic
................................................
and
information
(operating
hookups
...............................................
......•.•........•..........•................
factory-service
instructions)
..••......•....•..........•.....••....
••••.•••..•••....•..•...•.•.••....•.•••.
.•••.•••••••••••••••••••••••••
information
for
users
in
the
United
.•••.••••..••.•••....•.••
Kingdom
.•.•••••.•••...•
2
4
5
6
11
12
13
13
Page 4

READ
THIS
The
a
tape-monitor
or
receiver
more
than
choice.
in
the
The
next
for
your
new
in
the
signal
to
be
going
if
you've
loop,
If
leave
your
preamp
separate
leave
and
Out
the
choose
knob.
SOUND
let
sound
imager --connected
Push
corresponding
path.
gram
hooked
pass
The
1,
then
emitting
the
indicates
essors
lA
SOUND
These
processor(s)
Pushing
of
the
process
before
processor(s)
only,
FIRST
best
place
to
(record/play)
("preamp"
one
such
details
section,
now, simply
4-00X
path
to
and
connected
the
is
Input
Select
Select
the
See
"Usage
from
loop,
about
"Rear
note
to
be in
--
the
from
the
preamp
one
and
knob
program
FRONT
(see
facing
PROCESSORS 1 ,2,3.
you
switch
in
and
processor(s)
one
or
more
processor(s)
You will
through
up.
the
processor(s).
processors
2,
diode)
400X'
s
the
in
the
be
whichever
Leave
enter
then
3.
will
faceplate
presence
signal
PROCESSORS:PRE,
buttons
control
relative
"Pre"
deck,
puts
which
(equalize,
it
gets
recorded.
after
which
means
locate
your
loop
dbx 400X is in
in your
now on).
Tape
this
1 is
the
hookup
Jacks."
that
in
operation
signal
it.
4-00X
set
of
those
Rec
(or
whatever)
source
In
in
to
always
other
the
monitor
that
Out
with
Notes."
PANEL
page)
These
out
of
operation
--equalizer,
to
the
back
of
the
buttons
into
sending
the
musical
processors
the
button(s)
in
sequence,
The
yellow
light
LED
up.
Throughout
"route," a yellow
of
one
or
path.
POST,
the
position
to
your
tape
the
processor(s)
means
expand,
that
etc.)
"Post"
the
deck(s),
that
you
on
alter
preamp
If
you
obvious
are
given
order
--
that
has
words,
Tape
Tape
have
switches,
on
Tape
the
buttons
expander,
of
to
put
the
signal
are
out
to
of
course:
(light-
more
COPY.
of
the
deck(s).
ahead
you
can
the
signal
puts
the
playback
the
sound
have
for
is,
1
Rec
the
4-00X.
the
pro-
by-
LED
proc-
1.
when
"Copy"
essor 1 ,2,
master")
you're
for
listening
dubbing:
or 3 between
deck
and
to
it
places
the
recording
deck(s).
2 MONITOR:LINE,T APE 1
buttons
tor).
player,
"Tape"
trol
amp from
cates
green
(Decoding
monitor
NOISE
:COPY,
3A
The
(record)
your
unit.
monitoring
corded
NR
3B
The
encoding
inserted
cedure.
either
encoded)
deck.
cassette
example,
before
Leave
(deck-to-deck)
recording,
The
lights
involved,
stream"
to
"Line"
radio,
is
which
that
one
button
choose
your
signal
the
the
indicates
is
what
is your
TV
record
/VCR,
deck(s).
gets
4-00X. The
signal
that
explained
at a time.
returned
is
next.)
REDUCTION:DECODE:MONltor
and
:ENCODE:LINE
top
pair
of
buttons
or
dbx
or
Pushing
--provided
unit
have
bottom
separately
That
encoded
This is
decoder
other
of a
this
pair
and
decoding
is,
before
handy
(playback)
noise-reduction
both
in,
of
tape
while
your
simultaneous
of
buttons
functions
into
the
copy
or
decoded
iJeing
copied
for
of a dbx-encoded
to
play
over
your
you've
the
red
LED
up
from (after)
bottom
that
for
that
and
added
a dbx
buttons
dubbing
is, involving
under
the
function
similar
red
the
and
"Encode"
procedures.
the
tape.
signal
the
playing
,2,3.
to
Push
listen
and/or
or
other
These
buttons
yellow
being
it's
being
processed;
Push
or
choose
the
section
course,
it's
being
cassette
permit
a dubbing
master
(if
it
by
making
tape,
car
stereo
decoder
out
for
for
regular
no
dubbing.
whenever
ones
do so
encoder
Push
proc-
("copy
(receiving)
these
to
(moni-
CD
source;
con-
to
your
pre-
LED
indi-
decoded.
only
:COPY.
encoder
of
(NR)
permits
re-
deck
and
capability.
the
to
be
pro-
can
be
already
is
another
a Dolby-B
for
to
it.
direct
tape
button
it
is
"down-
in dubbing
the
one
or
-2-
Page 5

,r-'-·4
5A
5B
TAPE 1 ,2,3:COPY
these
tape
yellow
buttons
deck
for
LED will
and/or a signal
in
the
dubbing
and
the
copying
REC
SELECTOR:TAPE 1 ,TAPE
LINE or
The
which
the
the
The
which
tape
LEOs
been
it
has,
before
For
one
:COPY
top
row
deck(s)
line
input
400X.
second
deck(s)
played
indicate
inserted
you
it
decks
of
the
of
row
on
can
gets
that
unused
MASTER.
to
choose
dubbing.
light
processor
path,
deck(s).
and/or
buttons
you
want
(record
of
buttons
do
the
the
master
whether
before
encode
to
the
are
turned
Copy
the
The
if
the
(respectively)
between
:ENCODE
lets
to
use
player,
lets
copying
deck.
the
the
receiving
the
signal,
copying
off:
Master
Push
one
"Copy
green
NR
decoder
copy
2,T
Master"
and/or
master
APE
CANCEL.
you
choose
for
recording
radio,
you
etc.)
choose
(dubbing) of a
The
NR
encoder
deck.
of
course,
deck.
press
any
buttons,
of
are
red
has
3:
to
If
5C
then
press
powered
them
any
deck
For
from
adverse
example,
but
empty),
(3 is
preferable),
Note:
for
this
This
the
yet
decks,
button
the
before
recording
switching
bottom
encoding
keep
as
will
Noise
setting.
This
means,
dbx
copies
receiving
want
to
the
deck.
your
interaction
if
not
the
push in
you
or
Copy
button
(Doing
this
system,
you're
using
Tape 2 one
Copy
Master:Tape 2 or
and
also
turn
on
playing,
for
disconnects
thereby
with
Copy:Tape
the
remember
arrangement.
row
lets
you
individually
process
the
function
above.
selectively
to a given
active
In
other
words,
defeat
Reduction:Encode:Copy
for
of a
decks
make
example,
particular
except
a Dolby
that
tape
one
on which you
copy.
each
your
your
(and
unused
deck
for
other
the
you
on
un-
preventing
preamp.)
Tape
Tape
1
3 is
3
2.
deck(s)
to
undo
cancel
and
each
action
of
button
can
make
all
the
lA
3B
5B
5C
AC LINE VOLTAGE REQUIREc\-\ENT I'lDICATOR.
The
recessed
nominal
400X
ac
has
AC POWER CABLE.
any
50
or
correct
line
LINE VOLT AGE
requires
indica
line
voltage
been
set
60Hz
ac
voltage,
requirement.
a maximum
tor
displays
for which
at
the
factory.
Connect
power
as
shown by
source
of 5 watts
the
the
this
cable
of
the
the
The model
ac
power.
to
ac
400X
-3-
Page 6

4
REAR
right
face
See
the
facing
the
unit
Note
also
point
the
in
other
Finally,
use
it
for
hookup
page.
itself
the
if
the
Note
is
that
direction
unit)
your
right
illustrations
an
the
and
cables
1 LINE. This is
400X
to
your
to
the
400X's
400X's
Line
Out,
JACKS,
to
left
the
back
that
the
overhead,
triangles
of
signal
"In"
(From
have a side
channel.
where
preamp.
Line
In
left
as
you
panel
on
this
one
from
not a rear,
below
flow:
the
you
hook
Connect
and
its
to
left,
and
the
"Out"
other
with
up
its
Tape
right
3
the
the
400X's
unit).
red
the
Tape
In**
to
top
of
view.
(To
plugs,
model
to
right.
jacks
Out*
the
2
If
you
have a current
NX-40),
the
fastest
non-dbx
Dolby
Do
unit
is
the
more
as
Don't
study
facing
nomenclature
i~R
ones)
the
same
(122/4/8).
most
easily
left
and
use
page;
units
have
if you
complicated,
if you
jacks 3 and 4 as
the
Record
numbered 2 and
of
jacks
numbered 1 and
left
empty
(nothing
dbx
the
appropriate
that's
the
to
(e.g.,
similar
have a previous
In
the
case
designate
side's
4 or
the
plugged
unit
easiest
follow.
the
old
labeling.
of
the
hookup
jacks 1 and
right
pairs
Play
3;
they're
into
(222/4/8
hookup
and
Some
Advent
dbx NR
a 124,
(red).
of
side's
okay
them).
or
on
which
will
jacks
pairs
go
2
2
3
SOUND
your
See
order.
(To)
PROCESSOR
equalizer,
the
Usage
Connect
jacks
connect
(From).
Repeat
NOISE
you
(NR)
*Also
Rec,
**Also
tor,
for
REDUCTION
put
your
unit.
called
To
called
Playback,
Out(puts),
EOUI
P~N
COf'.U".£CTIONS
to
your
its
Output
Follow
each
dbx
Tape
Tape
etc.
T
imager,
Notes
the
appropriate
processor's
jacks
the
triangles.
processor.
(or
other)
Rec,
In(puts),
Play,
Tape
(In)
From
1,2,3.
for
This is
expander
advice
(etc.)
about
400X
Input,
to
the
400X's In
UNIT. This is
noise-reduction
RedOut),
(Out)
To
Play,
Tape,
Tape,
Tape
From
where
and
where
To
Moni-
Tape
go.
the
Out
Tape
etc.
4
If
you
have
will
help
Outs
and
the
former
latter
out,
labeled
(From)
cables
TAPE
where
Play.
note
(from
Encoder
according!
DECK 1
you
open-reel,
(processor
Connect
Inputs
its
as
of
Output
going
some
to
figure
its
decoder
are
called
Once
that
the -lOOX NR
the
,2,3.
connect
BetajVHS
plus VCR).
the
chosen
the
deck
to
the
out,
of
T
O,
FRO
M TO,
other
out
non-dbx
its
Ins
Record
you
have
rear)
Out
and
Decoder.
y.
This, of
your
decks --cassette,
hi-fi,
-!00:\
or
processor,
-lOOX's Tape
course).
FROM.I TO.
TAP£ 2 I r
LII'L
OVT
PVTS lf'o.PVT
encoder
and
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figured
facks
(To)
course,
or
Tape
AP£.:
2 T ..roE J
Llf'.l: L
S o..J""PPJTS l
NR
Ins and
Often
and
the
are
and
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dig
ital
Out
and
In
(same
FROM TO.
TAPE
f'.E.
L I
f'.FVTS
unit,
this
also
In
the
is
to
the
return
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Page 7

SOME
TYPICAL HOOKUPS
"Usage NoteS.
of
11
~~
L
dbx
NOISE
IN
OUT
~r---;;
R L R L
REDUCTION
G:_;
UNIT
R L
I
dbx and other components
with
various labeling;
SOURCE
also
see
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r PREAMP OR RECEIVER
E
~A~~
J
y
UT IN
L
[
------1·---
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0 0
CASSETTE
DECK
I
CASSETTE
DECK
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dbx
122
or
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c~JJ
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1
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2
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3
Examples of connect10ns for non-dbx
reductlon u
n1ts
Record
-
no,se-
-5-
Page 8

USAGE
To
the
order
As
monitor
the
400X
location
preamps,
and
in
the
Also
you will
preamp
(knobs,
switch)
that
you
the
impulse
NOTES
get
the
in
which
mentioned
loop(s) of
go in
for
the
although
400X
as
mentioned,
have
to
has
those
usually),
set
to
Tape 1 and
want
to
of
most
your
the
400X
.
leave
separate
you
listen
most
out
to
connect
earlier,
preamp.
first,
is in
if
you hook
the
must
to
people
of
the
dbx
your
other
the
400X
If
yours
leaving
the
to
Tape 1 switch
leave
use
and
so-called
it
use
"Input
the
route
is
the
the
up
the
Selector"
the
Rec
opposite.
model
will
second
there
400X
unit's
through
400X, you
equipment.
be
most
has
two
free
external-processor
you
lose
in
Tape 1 --to
(usually a button)
and
Input
Out
knob
the
must
useful
tape
loops,
for
the
flexibility
"Record
Selector
to
choose
400X.
We
gl
ve
if
it's
we
future.
(EP)
both
get
signal
ln.
However,
Out"
selection
knob (or
the
program
emphasize
some
thought
in (one of)
recommend
An
alternative
loop
of
certain
in
your
to
and
switches
tape-monitor
source
this
to
the
tape-
that
preamp
frorn
if
your
because
it
Now.
cause
ser.ds
1
(SP)
and
that
than
switch,
experiment
we
judgment
ful
enable
Equalizers
nominal
sound
of
sound
be
it
affects
the
program
to 2 to
must
experimentation
the
placed
J.
loop 1 gets
so
on.
loop
and
If a processor
three
that's
Since
emphasize
is
you
User-controlled
filter
of
the
speakers
processing
early
Once
If
the
If
the
proceeds
are
entirely
the
with
it's
called
to
find
settings--
musical
you've
what
sound
signal
corresponding
the
signal
button
to
has
its
possible.
place
switching
impossible
and
to
on
that
for
in
with
out
what
"graphic"
program
room.
be
done,
in
the
to
hooked
through
first,
is
disengaged
the
to
this
any
various
are
400X
up
the
changes
next.
own
put a fourth
it
before
suggest a "perfect"
section
complex
works
employed
as
This
so
's
you
the
button
after
tape-monitor
And
and
contains
combinations
best.
equalizers
to
correct
kind
of
if
you
signal
400X.
(up to)
which
or
if
unit
arrangement
by
equalization
follow
path,
can
is in,
left
one
after
(EQs)
some
the
obtain.
three
the
it's
out,
loop,
of
the
for
the
guidelines
and
for
large
the
probably
order
processor
passed
maximum
order
--commonly
people
practice,
becomes
As
noted,
connected
to
naturally,
of
course,
initial
processor
for
only. Your own good
of
your
sequences
as
irregularities
is
perhaps
in SP
important,
the
processors
in Sound
the
processor
the
signal
hookups
three
has a PrejPQst
flexibility:
with
PrejPost.
all
signal
stereo
much
your
loop
system.
of
hookups
having
to
the
equalizer
1.
model
change
in
most
-WOX
in
Processor
in
bypasses
of
more
you
can
processors,
will
one-octave
the
the
response
basic
should
be-
order,
loop 2,
Care-
However,
example
These
the
equalizers
automatic-equalization
for
a
sound
should
signal
such
processor
--whose
an
there
be
put
take
place,
use a test
EQ. (If
job is
for
after
are
automatic
to
make
in
the
last
downstream
signal
to
results
some
an
automatic
the
processor
from
do
their
won't
reason
equalizers--
speakers
loop,
it.
The
job,
and
be
correct.
you
find
equalizer,
-6-
the
dbx
and
room
flatter
so
that
no
further
reason
if
Thus SP
it
most convenient
everything
this
for
signal
loop
10/20
this
gets
3 is
will
and
20/20,
in
combination.
alterations
is
that
these
changed,
the
best
after
be
all
okay
if
for
the
to
you
of
place
place
I
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Page 9

make
The
response,
Mcintosh,
making
ternal-processor
amp
also
changing
sure
third
category
usually
etc.).
the
if
you
pertains
speaker
that that
final
have
to
processor
is
equalizers
at
one
or
Such a
correction.
(EP,
separates.
narrow-band
response
dedicated
SP,
etc.)
is
out
that
both
ends
It
might
loop,
(Follow
parametric
and
usually
or
bypassed
come
of
the
equalizer
be
placed
or
it
can
the
manufacturer's
or
left
during
with
your
audio
band
must
do
in a
tape-monitor
be
put
between
third-octave
to
one
setting.
the
equalization
speakers
(Allison, Bose,
its
work
directions.)
equalizers
to
after
preamp
improve
dbx, E V,
the
400X,
(Tape
and
This
used
process.)
their
2)
or
ex-
power
advice
only
for
Another
its
tape-monitor
(or
From
turns
corder
Tape
set
to
Bass
500)
ciencies
synthesizer
have
principally
that
the
smoothed-out
already
that
before
Dynamic-Range
predecessors),
models
matic
range
ible
noise
floor
is
desirable
Preamp
to
the
preamp's
In)
goes
In
(or
From
its
Tape
Reinforcers
A
subharmonic
--
should
in
the
gets
the
best
However,
to
the
low
frequencies
modified
process
an
Expanders,
EQ.
expanders
to
work
reduction
several
the
automatic
117/8/9,
The
with. A second
dB).
because
solution
loop.
to
Monitor.
follow a user-controlled
recording
the
possible
an
equalize
for
bass
Expanders
such
and
also
reasoning
should
(when
for
Your
Tape
Out),
Tape
the
400X'
Tape
Recorder
synthesizer
or
signal.
signal
automatic
speakers
created
system,
room/speaker
as
well
EQ.
as
a dbx 1
compressor
should
is
have
they
Therefore
many
this
is
preamp's
and
In.
Meanwhile,
s
Line:In,
broadcast
In
other
to
work
equalizer
should
and
the
as
boost
and
the
BX
/expander
be
located
similar
as
"correct"
reason
make
they
of
them
to
the
Out).
--the
by
synthesizer
irregularities.
like
soft
will
aren't
put
the
400X
Tape
Out
EQ's
Line
the
and
the
-WOX' s
Note
that
dbx 120 or
program-source
can
be
somewhat
words,
with.
the
it
Series
to
that
is
that
sounds
make
the
(the
dbx
come
after
after
synthesizer
should
Two, 3BX
/enhancers,
program-source
for
(in
frequency
dbx
softer
equalizers
quite
"inside"
goes
to
Out
(or
To
EQ's
Tape
Line:Out
the
speaker
its
predecessors
equalizer,
subharmonic
10/20
won't
be
bass
expanders,
as
or
a 120. The
will
have
Likewise,
placed
Series
such
processors.
response) a signal
they
quieter,
low in
the
speaker
the
speaker
Preamp
Out
(or To
returns
EQ
corrected
synthesizer
20/20)
reason
then
be
to
operate
other
after a program
Two,
as
the
EQ
at
least,
also
push down
noise
as
E(/s
Tape
Tape
itself
(the
so
that
before
or
other
reproduced
on a
components
or
4BX (or
previous
and
before
One,
dynamic-
provide
which
they
equalizer,
Line
In)
re-
Re-
to
the
EQ's
is
always
100,
11
defi-
the
should
EQ
used
for
this
is
by
signal
EQ
but
their
dbx
auto-
as
poss-
some
the
noise
sometimes
could
be.
in
In
O,
In
this
material
Feel
free
provement.
Finally,
the
expander
Imagers
These
They
are
sequence,
may
occasionally
to
switch
if
be
are
best
placed
some
the
order
you own
first.
both
the devices
after
combinations
result
everything
of
an
that
in
"surging"
equalizer
expander
alter
the
in
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and
stereo
the
of
EQ
settings,
in
the
sound
expander
and a bass
sound-processing
reinforcer,
image
--its
expanders,
at
various
to
see
if
there's
we
depth and width.
chain
and
program
frequencies.
an
im-
recommend
except
Page 10

automatic
phase
the
last
ward
and
is
say
that
equalizers
phase
relationships
either
only
speaker
together
if
used
equalizers,
relationships
in
changing
it
equalizes
between
(identically)
in
the
former
like
them.
of
course.
the
the
both
mode.
dbx
in
the
sound.
channels
Note
or
separately
20/20.
program
The
that
But
imagers
Imagers
signal,
reason
the
identically,
the
dbx
10/20
(differently),
still
do
their
so
dbx
doing
are
job by
they
must
20/20
no
harm
can
equalize
and
may
followed
modifying
have
can
be
to
follow
by
close
placed
the
phase
the
channels
an
imager
dedicated
the
to
after-
Reverb
Units
Like
thing
Playing
else
(Decoding)
You
the
current
model
the
model
record,
that
21
unit.
• • •
with a Model
If
you
400X's
the
the
encoded
discjtape
Your
processors);
and
the
Encode
should
be
out.
Then
ther
signal
coded
• • •
.
with
A
dbx
Reduction
encoded
must
for
button
in,
be
its
part,
disengaged
to
Tape.)
tapes
pushed
imagers,
but
automatic
can
play
220
series
preamp
have
one
Noise
400X's
SP
record
any
one
buttons
set
the
dbx
processing,
a Model
model
loop,
must
as
as
in
21
well
and
have
(at
reverb
dbx
devices
EQs
like
Records
dbx-encoded
(or NX-'+0)
decoder.
is
set
The
to
122, 124, 128,
of
these
Reduction
buttons
of
the
must
unit
if
encode/decode
Unit
may
signal
doesn't
three
be
for
disc
selected,
21
discjtape
noted.
as
one
its
Source).
dbx
In
this
records.
of
its
In/Out
(For a tape,
decoder,
should
the
dbx
go
20/20.
•••
records
with
noise-reduction
hookup
Phono
or
be
Tape
in.
and
and
Tape
222, 224, 228,
loop,
as
discussed
as
you
get
tampered
buttons
Everything
decoding
takes
place
too,
location
the
To play
Tape
buttons
button
pushed
of
toward
any
of
units,
the
operation
1 (if
or
units,
desire;
must
downstream
according
as
usual,
can
be
21
can
the
records,
must
be
In
and
course,
the
the
or
that's
NX-40
it
should
earlier.
the
Post
with
be
in; and
to
after
placed
be
pushed
its
the
very
end,
after
every-
previous
you
by
its
used
the
dbx 122/'+/8
can
use
of
switches
where
from
be
connected
To
play
button
any
of
both
the
must
the
the
these
instructions.
the
record
in
the
-+OOX\
to
play
400X's
in.
The
just
depend
400X
a dbx
be
signal
Oecode
buttons
is
Noise
back
Post
model
Nlonitor:TapejSource
second
button
is
or
the
is) .
in
the
in (so
Fur-
de-
dbx-
button
21,
pushed
on
If
you
want
Noise
SP
21's
amp
other
in
button
encoded
Reduction
loop --and
Record:Inputs:From
Tape
or
Monitor
(two
sets
Source
To
is
with
play
pushed
cassettes
With this setup, tapes of dbx-encoded records
to
use
loop is
only
the
Input
of
two)
the
noise-reduction
a dbx
in,
record
too,
this
your
occupied
first.
Preamp
jacks
jacks
alone.
now,
naturally,
way
as
21
In
the
well.
for
dbx-record
with
this
case,
Tape
return
Returning
button
400X's
and
-8-
some
connect
Output,
to
the
In.
Line
the
Post
decoding
other
NR
the
and
the
400X's SP:In.
to
the
front,
button
button
will
only
(andjor
unit),
it
may
400X
's
SP:Out
21's
Play:Outputs:To
Leave
the
21
is
pushed
is in. You
be
in,
can
recorded encoded,
the
go
in
jacks
the
21's
should
the
SP:l
play
400X's
the
first
to
Pre-
four
be
left
dbx-
the
to
Page 11

be
decoded
copy,
for
example),
on
playback.
push
To
Pre
tape
.
a dbx
record
in
decoded
form
(to
make
a Dolby
Through a Cassette
• • •
All
but a few
decoding
hooked
Monitor
Selector
playing
if
it's
sound
Second
in
the
er
loop.
second
Rec
Amp
equivalent.
or
equivalently
return
In
or
capability,
up in
to
the
buttons
Now
follow
dbx
all
the
processors
Noise-Reduction
If
you wish
400X'
s
The
unit's
Out
jacks,
Tape
(Monitor)
to
the
whatever.
one
of
deck's
out.
the
records.
way
down,
(in
to
Noise
dbx
unit's
From
and
The
second
named
second
See
Deck
cassette
too.
the
loop
instructions
(Don't
Post)
use a second
Reduction
Preamp
its
To
In
jacks
unit's
below;
decks
To
400X's
number,
forget
you
won't
connected
Units
To
Tape
(Tape)
Preamp
returns
unit's
go
From
it's
take
with
dbx
Noise
with
dbx
advantage
tape
loops,
and
leave
in your
to
turn
hear
the
to
the
noise-reduction
Unit
loop,
it
Recorder
Out(put)/Line
(Tape)
to
the
dbx
To
Tape
Record(er)
to
the
400X's
Tape
Record(er)
easier.
Reduction
noise
reduction
of
this
set
the
Sound
Decode/Encode
cassette
up
record.)
400X
should
Input
In(put)/Line
unit's
deck's
the
deck's
as
unit
go
(or
In(put)jFrom
From
In(put)/To
Encoder:In,
Out(put)/From
offer
feature
You
usual.
(say,
in
equivalent)
Out(put)jTo
Tape
when
Processors
owner's
recording-level
may,
an
the
dbx
Recorder
and
record-
the
to
and
all
the
manual
of
course,
outboard
unit's
jacks
Tape
Tape/Tape
its
tape-record-
go
RecjTo
Tape
Output
Decoder:Out
Tape/Tape
deck
Post,
Rec
for
control;
use
Dolby
to
Play
Rec
is
the
the
B)
the
Amp
jTo
or
Out
jacks
Play
When
system
connections
One-Way
of
aren't
record
sequence.
out,
For
more
("Single-Ended,"
A
noise-reduction
record
pops,
encoded,
decoder
using
and
help
and
clicks,
(if
dbx
noise
vice
versa.
with
following.
unit
scratches
should
be
you're
)-
0,
J;
C}
QJ
, .
-
reduction,
other
using one).
units'
"One-Pass")
that
works
etc.
placed
in
:
'
10"'
it
generally
nomenclature,
Noise-Reduction
on
playback
or
to
reduce
the
next
SP loop on
In
any
event,
is
best
see
Units
only,
steadier
the
it
should
to
the
to
noise
switch
section
decrease
in
400X
after
be
early
the
other
on
rear-jack
the
sources
a dbx
on in
sound
that
the
-9-
Page 12

Other
Processors
Some
because
it
headphone
not
go
against
and
user-controlled
EQs.
advice
Similarly
in
users
might
has a useful
listening,
guidelines
all
other
the
accompanying
want
filter
etc.
EQs
and
processors:
to
or
You will
already
before
instruction
put a second
two,
different
want
to
given.
That
bass
reinforcers,
experiment
manuals.
preamp
tone
controls,
experiment
is,
locate
with
in
one
of
channel
about
it
where
after
expanders,
care,
while
the400X's
blending
to
put
record
and
decoders
automatic
following
SP
loops
it
yet
any
for
Four-Channel
The
the
like
cannot
channel
more
but
than
the
switching
hookups
Using 400X
The
preamp
your
have
new
sources
will plug
400X,with
Using
the
A
warning
processors
(" uad")
400X is a
easily
after
one
400X
gets
Loops
400X's six
doesn't
video,
digital/YCR,
directly
no
cables
Pre
Button
is in
you
have
stereo
or
as
sound-processor
returning
recorders --expecially
readily
treble.
when
that
an<;i
this.
overloaded
Reinforcing
strong
has
wide
cassette
Always
bass
is
dynamics
desks.
go
easy
by
already
Ambience-Recover
(two-channel
be
routed
the
signal
a 400X
extremely
Extra
have
enough
through a single
processing
and
a 200X,
complicated.
Inputs
and/or
into
the
to
the
order
hooked
cassette
too
much
the
bass
about
pushing
up
to
decks,
boosting
(particularly,
present,
to
begin
with,
And using dbx
in
processing
component.
it
and
tape
of
its
own.
CD
player
particular
component
the
-+OOX
and
of a given
or
expanding
also
noise
sig
reduction
nals
Time-Dela
400X:
that
takes
is
possible
loops
This
may
sources.
"In
(from)"
from
in
the
Pre
in
front
even
of
the
synthesizing
the
will
saturate
in
before
taping.
S
stems
Rear-speaker
it's
best
place
to
can
via
do
multi-channel
be
used
well
be
Note
inputs
the
loop's
button,
your
very
placing
tape
best
frequency,
subharmonic
dynamic
even
taping
will
etc.
processors
to
do
these
the
400X. With
as
extra
the
case
that
playback
on
the
back
"Out
(to)"
the
decks.
of
those --can
particularly
frequencies)
range
the
of
newest
not
prevent
extra-
routing
inputs
if
you
of
jacks.
sound
All
in
material
tap~s
and
--
if
the
be
the
If
a
program
orchestral
old
record
allow
original.
tapes
But
respects--
straight,
without
Remember
added
during
Overdriving
Like
overdriven
large
input
can
produce
equalizers
volume
attention
from
controls
to
each
signal
is
sonically
broadcast, a heavily
with
to
be
source
that's
weak
bass--
made
material
clear,
Pre
processing.
that
any
then
that
sound
quiet,
improvements
playback.
tape
decks,
by
too
levels
more
when
set
are
the
maximum
processor,
successive
much
without
signal
to
boost
set
and
voltage.
distress,
at
its
any
past
unity
input-voltage
to
consider
deficient
compressed
careful
cleaner,
that
is
reasonably
dynamic
sound
Most
and
output
than
frequencies
gain.
moving
-10-
FM
use
of
wider,
and/or
which
processors
dbx
equipment
by
its
very
it
received.
and
Therefore
capacity
up
in
its
original
station,
form
an
unbalanced
processors during
and
better-balanced
good
to
begin
with
well-balanced --is
seem
necessary
(ones
nature,
of
spare
it's
of
all
earlier
corning
is
capable
This is
a good
equipment
any
can
most
dbx
also
preamps
idea
units
-a
dull
tape,
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than
in
these
best
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of
can
accepting
equipment
true
of
when
to
pay
downstream
that
appear
an
the
be
be
their
Page 13

relatively
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controls
equipment
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Page 15

WARRANTY
dbx
All
purchased
details,
The
questions
You
also
92-2522.
outside
consult
dbx
and
may
and
FACTORY
products
the
your
Customer
information
call
(617)
are
covered
USA
are
warranty
Service
on
964-3210
SERVICE
by a
valid
only in
card
or
Dept.
problems,
dbx
71
Chapel
Newton,
Attn:
Customer
during
limited
your
will
write
St.
Mass.
business
warranty
the
country
dealer
help
you
to:
02195 USA
Service
(warranties
of
/distributor.
use
this
hours
(USA
purchase
product.
Eastern
for
products
and
the
For
Time).
USA).
answers
The
For
to
Telex
is
Should
1)
of
purchase;
2)
3) We
Service
If
address
it
Repack
Send
the
strongly
whenever
you
live
of
the
become
the
unit,
unit
recommend
possible.
outside
nearest
necessary
including a note
freight
authorized
the
prepaid
that
USA,
to
have
to
you
contact
repair
your
equipment
with a description
the
above
insure
the
center.
address,
the
nearest
package
dbx
serviced
of
the
marking
and
dealer
at
the
problem
it
"Attn:
send
it
or
distributor
factory:
and
Repairs."
by
United
the
for
date
Parcel
the
-13-
Page 16

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Japan
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