dbx 400 Owner's manual

dbx 400 Owner's manual
 Model 400
Program-Route Selector
Instruction Manual
WARNING: TO PREVENT FIRE OR SHOCK HAZARD,
DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE.
"dbx" is a registered trademark of dbx Inc., Newton, Mass., USA
INSPECTION and INSTALLATION
Your unit was carefully packed at the factory in a carton designed to protect
it. Nevertheless, we recommend examining both carton and contents for any signs
of damage. If there is such evidence, don't destroy the carton or any of the packing
material, and notify your dbx dealer immediately.
In any case it is a good idea to save the carton and packing materials should
you ever need to ship your unit in the future.
In addition to a model 400 and this instruction manual, the carton should
contain a set (two pairs) of hookup cables with conventional RCA phono (pin) plugs,
mounting brackets, and a warranty /registration card.
The 400 is mountable into any standard 19-inch (48.3-cm) equipment rack with
the supplied brackets. No special cooling or ventilation is required in any installa-
tion; other components may be stacked above or below the 400 provided they don't
generate excessive heat.
CONTENTS
Front panel (operating instructions) .
Rear jacks (connections) .
Some typical hookups
Usage notes .......
Block diagram . « « « «
SchematlC .. +...
Warranty and factory-service information
Important information for users in the United Kingdom.
E я RISK OF ELECTRIC SHOCK | I
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00 NOT REMOVE COVER (OR BACK}
NO USER-SERVICEABLE PARTS INSIDE
AEFER SEAVICING TO QUALIFIER SERVICE PERSONNEL
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The lightning flash with arrowhead
symbol, within an equilateral triangle,
is intended to alert the user to the
presence of uninsulated “dangerous
voltage” within the products encio-
sure that may be of sufficient magni-
tude to constitute a risk of electric
shock to persons,
The exclamation point within an
eduilaterai triangie is intended to
alert the user to the presence of
important operating and maintenance
{servicing} instructions in the litera-
ture accompanying the appliance.
READ THIS FIRST
The best place to locate your dbx 400 is in
a tape-monitor (record/play) loop in your preamp
or receiver ("preamp" from now on). If you have
more than one such loop, Tape | is the obvious
choice. The details about this hookup are given
in the next section, "Rear Jacks."
For now, simply note that in order for your
new 400 to be in operation -- that is, in the sig-
nal path -- the signal always has to be going to
and from it. In other words, if you've connected
the 400 in the Tape | loop, leave the preamp set
to monitor Tape |. If your preamp is one of those
that have separate Input Select and Rec Out
switches, leave the Select knob (or whatever) on
Tape 1 and choose the program source with the
Rec Out knob. See "Usage Notes."
FRONT PANEL
(see facing page) 3A
l SOUND PROCESSORS 1,2,3. These buttons
let you switch in and out of operation the
sound processor(s) -- equalizer, expander,
imager -- connected to the back of the 400.
Push one or more of the buttons to put the
corresponding processor(s) into the signal 3B
path. You will be sending the musical pro-
gram through whichever processors are
hooked up. Leave the button(s) out to by-
pass the processor(s). |
The processors enter in sequence, of course:
1, then 2, then 3. The yellow LED (light-
emitting diode) will light up. Throughout
the 400's faceplate "route," a yellow LED
indicates the presence of one or more proc-
essors in the signal path.
IA SOUND PROCESSORS:PRE, POST, COPY.
These buttons control the position of the
processor(s) relative to your tape deck(s).
Pushing "Pre" puts the processor(s) ahead
of the deck, which means that you can
process (equalize, expand, etc.) the signal
before it gets recorded. "Post" puts the
processor(s) after the deck(s), on playback
only, which means that you alter the sound
when you're listening to the tape. Push
"Copy" for dubbing: it places signal proc-
essor 1,2, or 3 between the playing ("copy
master") deck and the recording (receiving)
deck(s).
MONITOR:LINE, TAPE 1,2,3. Push these
buttons to choose what to listen to (moni-
tor). "Line" is your record and/or CD
player, radio, TV/VCR, or other source;
"Tape" is your deck(s). These buttons con-
trol which signal gets returned to your pre-
amp from the 400. The yellow LED indi-
cates that the signal is being processed; the
green one indicates that it's being decoded.
(Decoding is explained next.) Push only one
monitor button at a time.
NOISE REDUCTION:DECODE:MONItor or
:COPY, and :ENCODE:LINE or :COPY.
The top pair of buttons choose the encoder
(record) or decoder (playback) section of
your dbx or other noise-reduction (NR)
unit. Pushing both in, of course, permits
monitoring of a tape while it's being re-
corded -- provided your cassette deck and
NR unit have this simultaneous capability.
The bottom pair of buttons permit the
encoding and decoding functions to be
inserted separately into a dubbing pro-
cedure. That is, the copy master can be
either encoded or decoded (if it already is
encoded) before being copied by another
deck. This is handy for making a Dolby-B
cassette of a dbx-encoded tape, for
example, to play over your car stereo
before you've added a dbx decoder to it.
Leave the bottom buttons out for direct
(deck-to-deck) dubbing and for regular tape
recording, that is, involving no dubbing.
The red LED under the "Encode button
lights up for that function whenever it is
involved, and similar red ones do so "down-
stream" from (after) the encoder in dubbing
procedures.
ЗА
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TAPE 1,2,3:COPY MASTER. Push one of
these buttons to choose the "Copy Master"
tape deck for dubbing. The green and/or
yellow LED will light if the NR decoder
and/or a signal processor (respectively) are
in the dubbing path, between copy master
and the copying deck(s).
REC SELECTOR:TAPE 1,TAPE 2,TAPE 3:
LINE or :COPY and/or :ENCODE CANCEL.
The top row of buttons lets you choose
which deck(s) you want to use for recording
the line input (record player, radio, etc.) to
the 400. 5C
The second row of buttons lets you choose
which deck(s) do the copying (dubbing) of a
tape played on the master deck. The red
LEDs indicate whether the NR encoder has
been inserted before the receiving deck. If
it has, you can encode the signal, of course,
before it gets to the copying deck.
For decks that are turned off: press any
one of the unused Copy Master buttons,
then press the Copy button for each un-
powered deck. (Doing this disconnects
them from your system, thereby preventing
any adverse interaction with your preamp.)
For example, if you're using your Tape |
deck but not the Tape 2 one (and Tape 3 is
empty), push in Copy Master:Tape 2 or 3
(3 is preferable), and also Copy:Tape 2.
Note: before you turn on the unused deck(s)
for recording or playing, remember to undo
this switching arrangement.
This bottom row lets you individually cancel
the encoding process to a given deck and
yet keep the function active for other
decks, as above. In other words, each
button will selectively defeat the action of
the Noise Reduction:Encode:Copy button
setting.
This means, for example, that you can make
dbx copies of a particular tape on all the
receiving decks except one on which you
want to make a Dolby copy.
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AC LINE VOLTAGE REQUIREMENT INDICATOR
The recessed indicator displays the nominal AC line voltage for which the 400 has been set at the factory.
AC POWER CABLE
Connect this cable to any 50 or 60 Hz AC power source of the correct line voltage, as shown by the AC
LINE VOLTAGE Requirement. The Model 400 requires a maximum of 5 watts AC power.
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4 3 2 1
REAR JACKS,
right to left as you
face the back panel
See the hookup illustrations on this and the
facing page. Note that the one from the top of
the unit itself is an overhead, not a rear, view.
Note also that the triangles below the 4#00's jacks
point in the direction of signal
flow: "Out" (To
the other unit) and "In" (From the other unit).
Finally, if your cables have a side with red plugs,
use it for the right channel.
l
LINE. This is where you hook up the model
400 to your preamp. Connect its Tape Out*
to the 400's Line In and its Tape In** to the
400's Line Out, left to left, right to right.
SOUND PROCESSOR 1,2,3. This is where
your equalizer, imager, expander (etc.) go.
See the Usage Notes for advice about the
order. Connect the appropriate 400 Out
(To) jacks to your processor's Input, and
connect its Output jacks to the 400's In
(From). Follow the triangles.
Repeat for each processor.
NOISE REDUCTION UNIT. This is where
you put your dbx (or other) noise-reduction
(NR) unit.
YAlso called Tape Rec, Rec(Out), To Tape
Rec, To Tape In(puts), (Out) To Tape, etc.
**Also called Play, Tape Play, Tape Moni-
tor, Playback, (In) From Tape, From Tape
If you have a current dbx unit (222/4/8 or
NX-40), study the appropriate hookup on
the facing page; that's the easiest and
fastest nomenclature to follow. Some
non-dbx NR units (e.g., the old Advent
Dolby ones) have similar labeling.
Do
the same if you have a previous dbx NR
unit (122/4/8). In the case of a 124, which
is the most complicated, the hookup will go
more easily if you designate jacks | and 2
as left and jacks 3 and 4 as right (red).
Don't use the Record side's pairs of jacks
numbered 2 and 4 or the Play side's pairs
of jacks numbered 1 and 3; they're okay
left empty (nothing plugged into them).
If you have some other non-dbx NR unit, it
will help to figure out its encoder Ins and
Qu
ts and its decoder Ins and Quts. Often
the former are called Record and the
latter Play. Once you have figured this
out, note that the 400 NR jacks are also
labeled (from the rear) Out (To) and In
(From) Encoder and Decoder. Connect the
cables accordingly.
4 TAPE DECK 1,2,3. This, of course, is
where you connect your decks -- cassette,
open-reel, Beta/VHS hi-fi, or digital
(pr
ocessor plus VCR).
Connect the chosen 400 Tape Out to the
Inputs of the deck or processor, and return
its Output to the 400's Tape In (same one
PREAMP OR RECEIVER
Out(puts), etc. as going out, of course).
FROM! TO: !FROM:! TO: |FROM: TO: | FROM: TO: |FROM:| TO: |FROM:| TO: | FROM| TO: FROM: TO: |FROM:| TO:
TAPE TAPE PROC, 1 PROC. 1] PROC. 2 | PROC. 2] PROC. 3 PROC. 3 TO FROM TO FROM TAPE | | TAPE 1 | TAPE 2 | TAPE 2 TAPE 3 TAPE 3
REAR PANEL | MONITOR] MONITOR | LINE LINE LINE LINE LINE LINE TAPE TAPE | PREAMP | LINE LINE LINE LINE LINE LINE
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SOME TYPICAL HOOKUPS of dbx and other components with various labeling; also see
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USAGE NOTES
To get the most out of the dbx model 400, you must give some thought to
the order in which to connect your other equipment.
As mentioned earlier, the 400 will be most useful if it's In (one of) the tape-
monitor loop(s) of your preamp. If yours has two tape loops, we recommend that
the 400 go in the first, leaving the second free for the future. An alternative
location for the 400 is in the so-called external-processor (EP) loop of certain
preamps, although if you hook it up there you lose flexibility both In your preamp
and in the 400.
Also as mentioned, to use the 400 in Tape | -- to get signal to and from it --
you will have to leave the Tape | switch (usually a button) in. However, if your
preamp has those separate "Input Selector" and "Record Out" selection switches
(knobs, usually), you must leave the unit's Input Selector knob (or tape-monitor
switch) set to Tape | and use the Rec Out knob to choose the program source
that you want to listen to and route through the 400. We emphasize this because
the impulse of most people is the opposite.
Now. Once you've hooked up the 400, the order becomes important, be-
cause it affects what sound changes you can obtain. As noted, the model 400
sends the program signal through the (up to) three connected processors in order,
| to 2 to 3. If the corresponding button is in, the processor in Sound Processor
(SP) loop | gets the signal first, after which it's passed to the processor in loop 2,
and so on. If the button is disengaged or left out, naturally, the signal bypasses
that loop and proceeds to the next.
If a processor has its own tape-monitor loop, of course, hookups of more
than three are entirely possible. And if one of the initial three has a Pre/Post
switch, that's the place to put a fourth unit for maximum flexibility: you can
experiment with switching it before and after the processor with Pre/Post.
Since it's impossible to suggest a "perfect" order for all signal processors,
we must emphasize that this section contains guidelines only. Your own good
judgment is called for in any complex arrangement of your stereo system. Care-
ful experimentation with various combinations and sequences of hookups will
enable you to find out what works best.
Equalizers
User-controlled "graphic" equalizers (EQs) — commonly having one-octave
nominal filter settings -- are employed by some people as much to change the
sound of the musical program as to correct for large irregularities in the response
of the speakers and room. This kind of equalization is perhaps the most basic
sound processing to be done, so if you follow the practice, your equalizer should
be placed early on in the 400's signal path, probably in SP loop 1.
However, there are automatic equalizers -- the dbx 10/20 and 20/20, for
example -- whose job is to make the speakers and room flatter in combination.
These should be put in the last processor loop, so that no further alterations of
the signal take place, downstream from it. The reason for this is that these
equalizers use a test signal to do their job, and if this signal gets changed, the
automatic-equalization results won't be correct. Thus SP loop 3 is the best place
for such an EQ. (If for some reason you find it most convenient after all to place
a sound processor after an automatic equalizer, everything will be okay if you
-6-
make sure that that processor is out or bypassed during the equalization process.)
The third category is equalizers that come with your speakers to improve their
response, usually at one or both ends of the audio band (Allison, Bose, dbx, EV,
Mcintosh, etc.). Such a dedicated equalizer must do its work after the 400,
making the final correction. It might be placed in a tape-monitor (Tape 2) or ex-
ternal-processor (EP, SP, etc.) loop, or it can be put between preamp and power
amp if you have separates. (Follow the manufacturer's directions.) This advice
also pertains to narrow-band parametric or third-octave equalizers used only for
changing speaker response and usually left to one setting.
Another solution for this is to put the 400 "inside" the speaker equalizer, in
its tape-monitor loop. Your preamp's Tape Out goes to the speaker EQ's Line In
(or From Preamp Tape Out), and the EQ's Line Out (or To Preamp Tape In) re-
turns to the preamp's Tape In. Meanwhile, the EQ's Tape Out (or To Tape Re-
corder In) goes to the 400's Line:In, and the 400's Line:Out returns to the EQ's
Tape In (or From Tape Recorder Out). Note that the speaker EQ itself is always
set to its Tape Monitor.
Bass Reinforcers
A subharmonic synthesizer -- the dbx 120 or its predecessors (the 100, 110,
500) — should follow a user-controlled program-source equalizer, so that defi-
ciencies in the recording or broadcast can be somewhat corrected before the
synthesizer gets the signal. In other words, the subharmonic synthesizer should
have the best possible signal to work with.
However, an automatic equalizer (the dbx 10/20 or 20/20) or other EQ used
principally to equalize speakers should come after a 120. The reason for this is
that the low frequencies created by the synthesizer will then be reproduced by
the smoothed-out system, and the synthesizer won't have to operate on a signal
already modified for room/speaker irregularities. Likewise, other components
that process the bass as well as boost it should be placed after a program EQ but
before an automatic EQ.
Dynamic-Range Expanders and the like
Expanders, such as a dbx 1BX Series Two, 3BX Series Two, or 4BX (or their
predecessors), and compressor /expander/enhancers, such as the previous dbx
models 117/8/9, also should be located after program-source EQ and before auto-
matic EQ. The reasoning is similar to that for bass processors. One, dynamic-
range expanders should have as "correct" (in frequency response) a signal as poss-
ible to work with. A second reason is that dbx expanders, at least, provide some
noise reduction (when they make soft sounds softer they also push down the noise
floor several dB). Therefore they will make equalizers quieter, which sometimes
is desirable because many of them aren't quite as low in noise as they could be.
In this sequence, some combinations of EQ settings, expanders, and program
material may occasionally result in "surging" in the sound at various frequencies.
Feel free to switch the order of equalizer and expander to see if there's an im-
provement.
Finally, if you own both an expander and a bass reinforcer, we recommend
the expander be first.
Imagers
These are the devices that alter the stereo image -- its depth and width.
They are best placed after everything in the sound-processing chain except
-7-
automatic equalizers like the dbx 20/20. Imagers do their job by modifying the
phase and phase relationships in the program signal, so they must have close to
the last say in changing the sound. The reason the dbx 20/20 can be placed aîter-
ward is that it equalizes both channels identically, doing no harm to the phase
relationships between them. Note that the dbx 10/20 can equalize the channels
either together (identically) or separately (differently), and may follow an imager
only if used in the former mode. But imagers still are followed by dedicated
speaker equalizers, of course.
Reverb Units
Like imagers, reverb devices should go toward the very end, after every-
thing else but automatic EQs like the dbx 20/20.
Playing (Decoding) dbx Records . . .
You can play dbx-encoded records with any of the previous dbx 122/4/8 or
the current 220 series (or NX-40) noise-reduction units, or you can use just the
model 21 disc/tape decoder. The hookup and the operation of switches depend on
the unit. Your preamp is set to Phono and Tape | (if that's where the 400 is).
...Witha Model 122, 124, 128, or 222, 224, 228, or NX-40
If you have one of these encode/decode units, it should be connected in the
model 400'a Noise Reduction Unit loop, as discussed earlier. To play a dbx
record, the 400's SP buttons may be as you desire; the Post button must be in (so
that the encoded record signal doesn't get tampered with by any of the signal
processors); any one of the three Tape buttons must be in; and both the Decode
and the Encode buttons must be in. Everything downstream from these buttons
should be out.
Then set the dbx unit for disc decoding according to its instructions. Fur-
ther signal processing, if selected, takes place as usual, aíter the record is de-
coded.
. « » With a Model 21
A dbx model 21 disc/tape decoder, too, can be placed in the 400's Noise
Reduction loop, as noted. In this location the 21 can be used to play back dbx-
encoded tapes as well as dbx records. To play the records, the 400's Post button
must be pushed in and one of its Tape buttons must be pushed in. The model 21,
for its part, must have its In/Out button pushed In and its Monitor:Tape/Source
button disengaged (at Source). (For a tape, of course, the second button is pushed
in, to Tape.)
If you want to use your 21 for dbx-record decoding only (and/or the 400's
Noise Reduction loop is occupied with some other NR unit), it may go in the first
SP loop — and only the first. In this case, connect the 400's SP:Out jacks to the
21's Record:Inputs:From Preamp Tape Output, and the 21's Play:Outputs:To Pre-
amp Tape or Monitor Input jacks return to the 400's SP:In. Leave the 21's four
other (two sets of two) jacks alone. Returning to the front, the 21 should be left
in Source with the noise-reduction button In.
To play a dbx record now, the 400's Line button is pushed in, the SP:l
button is pushed in, too, naturally, and the Post button is in. You can play dbx-
encoded cassettes this way as well.
With this setup, tapes of dbx-encoded records will be recorded encoded, to
be decoded on playback. To tape a dbx record in decoded form (to make a Dolby
copy, for example), push Pre.
. . . Through a Cassette Deck with dbx Noise Reduction
All but a few cassette decks with dbx noise reduction offer record-
decoding capability, too. To take advantage of this feature when the deck is
hooked up in one of the 400's tape loops, set the Sound Processors to Post, the
Monitor to the deck's loop number, and leave Decode/Encode and all the Rec
Selector buttons out.
Now follow the instructions in your cassette deck's owner's manual for
playing dbx records. (Don't forget to turn up the deck's recording-level control;
if it's all the way down, you won't hear the record.) You may, of course, use the
sound processors (in Post) connected to the 400 as usual.
Second Noise-Reduction Units
If you wish to use a second noise-reduction unit (say, an outboard Dolby B)
in the 400's Noise Reduction Unit loop, it should go in the dbx unit's tape-record-
er loop. The dbx unit's To Tape Recorder Input (or equivalent) jacks go to the
second unit's From Preamp (Tape) Out(put)/Line In(put)/From Tape Rec/To Amp
Rec Out jacks, and its To Preamp (Tape) In(put)/Line Out(put)/To Tape Play /To
Amp Tape (Monitor) In returns to the dbx unit's From Tape Recorder Output or
equivalent. The second unit's To Tape Record(er) In(put)/To Tape/Tape Rec Out
or equivalently named jacks go to the 400's Encoder:In, and its Decoder:Out jacks
return to the second unit's From Tape Record(er) Out(put)/From Tape/Tape Play
In or whatever. See below; it's easier.
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When using dbx noise reduction, it generally is best to switch the other
system out, and vice versa.
For more help with other units' nomenclature, see the section on rear-jack
connections and following.
One-Way ("Single-Ended," "One-Pass") Noise-Reduction Units
À noise-reduction unit that works on playback only, to decrease the sound
of record pops, clicks, scratches etc. or to reduce steadier noise in sources that
aren't encoded, should be placed in the next SP loop on the 400 after a dbx
record decoder (if you're using one). In any event, it should be early on in the
sequence.
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Other Processors
Some users might want to put a second preamp in one of the 400's SP loops
because it has a useful filter or two, different tone controls, channel blending for
headphone listening, etc. You will want to experiment about where to put it yet
not go against guidelines already given. That is, locate it aiter record decoders
and user-controlled EQs and before bass reinforcers, expanders, and automatic
EQs. Similarly all other processors: experiment with care, while following any
advice in the accompanying instruction manuals.
Four-Channel ("Quad"), Ambience-Recovery, Time-Delay Systems, etc.
The 400 is a stereo (two-channel) component. Rear-speaker processors and
the like cannot easily be routed through a single 400; it's best to do these extra-
channel hookups after the signal processing that takes place via the 400. With
more than one 400 or a 400 and a 200, it is possible to do multi-channel routing —
but the switching gets extremely complicated.
Using 400 Loops as Extra Inputs
The 400's six sound-processor and tape loops can be used as extra inputs if
your preamp doesn't have enough of its own. This may well be the case if you
have new video, digital/VCR, and/or CD player sources. Note that playback
sources will plug directly into the particular "In (from)" inputs on the back of the
400, with no cables returning to the component from the loop's "Out (t0)" jacks.
Using the Pre Button
A warning is in order about pushing in the Pre button, placing the sound
processors you have hooked up to the 400 in front of your tape decks. All
recorders -- expecially cassette decks, and even the very best of those -- can be
readily overloaded by too much boosting of a given frequency, particularly in the
treble. Reinforcing the bass (particularly, synthesizing subharmonic frequencies)
when strong bass is already present, or expanding the dynamic range of material
that has wide dynamics to begin with, also will saturate even the newest tapes
and cassette desks. And using dbx noise reduction in taping will not prevent
this. Always go easy in processing signals before taping.
If a program signal is sonically deficient in its original form — a dull
orchestral broadcast, a heavily compressed FM station, an unbalanced tape, an
old record with weak bass -- then careful use of processors during taping may
allow tapes to be made that sound cleaner, wider, and better -balanced than the
original. But source material that is reasonably good to begin with in these
respects -- that's clear, quiet, dynamic and/or well-balanced -- is best recorded
straight, without Pre processing.
Remember that any improvements which seem necessary can always be
added during playback.
Overdriving
Like tape decks, successive sound processors (ones coming after) can be
overdriven by too much voltage. Most dbx equipment is capable of accepting
large input levels without distress, and by its very nature, most dbx equipment
can produce more signal at its output than it received. This is also true of
equalizers when set to boost any frequencies and of spare preamps when their
volume controls are set past unity gain. Therefore it's a good idea to pay
attention to the maximum input-voltage capacity of all equipment downstream
from each processor, and to consider moving up earlier any units that appear
-10-
relatively easier to overdrive. One symptom is harsh, grating distortion in the
sound. Reduce the outputs of earlier processors and begin thinking about
rearranging the order of the units.
A final caution: whenever you rearrange processors (or other equipment),
be sure that all volume controls are all the way down and that everything is
turned off. After reconnections are made and the units are turned back on, turn
the volume controls back up slowly, to allow yourself time to react before doing
damage to equipment connected to the 400, to amplifiers, to speakers (especially
speakers) -- or to your ears.
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-12-
WARRANTY and FACTORY SERVICE
All dbx products are covered by a limited warranty; for details, consult your
warranty /registration card or your dealer.
The dbx Customer Service Dept. will help you use this product. For answers to
questions and information on problems, write to:
dbx Inc.
71 Chapel St.
Box 100C
Newton, Mass. 02195 USA
Attn: Customer Service
You also may call (617) 964-3210 during business hours (Eastern time). The Telex is
92-2522.
Should it become necessary to have your equipment serviced, call this toll-free
number to get a Return Authorization: 1-800-323-4353. No units will be accepted with-
out this authorization. After you have your return authorization, repack the unit, includ-
ing a note with your name, address, phone number, and a description of the problem.
Send the unit freight prepaid to the address given at the 800 number. (Continue to send
inquiries to the Customer Service Dept., however.)
We strongly recommend that you insure the package and send it by United Parcel
Service.
If you live outside the USA, contact your dbx dealer for the address of the nearest
authorized repair center.
FOR USERS IN THE UNITED KINGDOM
Important
The wires in this mains lead are coloured in accordance with the following code:
Blue: Neutral
Brown: Live.
As the colours of the wires in the mains lead of this apparatus may not correspond
with the coloured markings identifying the terminals in your plug, proceed as follows:
The wire that is coloured blue must be connected to the terminal
that is marked with the letter N or coloured black;
The wire that is coloured brown must be connected to the terminal
that is marked with the letter L or coloured red.
Ensure that all terminals are securely tightened and that there are no loose strands
of wire.
Warning
This unit must be protected by a 3-amp fuse, preferably using a fused plug.
Also, do not remove the cover without first disconecting the unit from the mains
supply.
For Information and Service
Please write to: Harman UK Ltd.
Mill St.
Slough
SL2 5DD
Berkshire, England
The telephone is 0753 769 11.
-13-
Printed in Japan
11832M-600999 R-1023A
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