Symetrix 422 User manual

422
422 Stereo AGC/Leveler
Users Guide

422
Table of Contents
Chapter 1 Introduction 1
Chapter 2 Operator Safety Summary 2
Chapter 3 Front & Rear Panel Overview 3
Chapter 4 Installation
Chapter 5 Operation 7
Chapter 6 Specifications 9
Chapter 7 Troubleshooting 10
Chapter 8 Warranty & Service 11
Appendix A Remote Bypass Wiring 13
Appendix B Declaration of Conformity 14
422 Stereo AGC/Leveler User’s Guide
© August 2000 Symetrix, Inc.
All rights reserved.
Printed in the United States of America
Symetrix Part Num er 53422-0A02
The information in this guide is su ject to change
without notice. Symetrix, Inc. shall not e lia le
for technical or editorial errors or omissions
contained herein; nor is it lia le for incidental or
consequential damages resulting from the
furnishing, performance, or use of this material.
Mention of third-party products is for informa-
tional purposes only and constitutes neither an
endorsement nor a recommendation. Symetrix
assumes no responsi ility with regard to the
performance or use of these products.
Under copyright laws, no part of this user guide
may e reproduced or transmitted in any form
or y any means, electronic or mechanical,
without permission in writing from Symetrix,
Inc. If, however, your only means of access is
electronic, permission to print one copy is here y
granted. Permission to copy the Architects and
Engineers Specificiations for written proposals
specifying equipment for sound reinforcement
systems is, also, granted.
Symetrix, Inc.
6408 216th St. SW
Mountlake Terrace WA 98043
USA
Tel:[phone]
Fax:[phone]
We : www.symetrixaudio.com
Email: [email protected]

422
1
IntroductionChapter 1
Front panel
Rear panel
Congratulations on your decision to use a Symetrix model 422 Stereo AGC/Leveler. The 422 has
been designed to give rofessional audio users unequaled erformance, ease of use, and reliability.
This manual will guide you through installation and o eration of the 422, and rovide valuable ti s
on how to interface with other equi ment in your system.
The 422 is a singular solution for controlling un redictable stereo (or monaural) audio levels in a
wide variety of audio systems. A lication environments include broadcast, recording, ta e
du lication and installed foreground and background systems just to name a few. The 422 excels at
subtly and unobtrusively bringing level divergent audio into a target window , resulting in greater
intelligibility and informational erce tion. Unlike com ressor/limiters, which are effective at
reducing sounds that are too loud ( ushing down from the to only), the 422 rovides both
downward com ression and u ward leveling by gently adding gain to low level signals until a
target level is reached.
The 422 em loys advanced analog signal rocessing technology executed with high quality
industrial grade com onents to meet, or exceed, the highest rofessional audio industry standards
in terms of headroom, low noise and distortion, and su erb sonic qualities.
The 422's logical control anel holds no hidden sur rises. The roduct is easy to learn and sim le
to use. In the sections that follow, you’ll find information on installation, o eration, and s ecific
a lications of the 422.
We recommend that you read this manual from cover to cover. Somewhere between the confines of
the two covers you should find the answers to most of your questions. If not, lease feel free to
contact our Customer Service de artment via hone, fax, or e-mail for answers to your questions.
The numbers are:
Tele hone:[phone]
Fax:[phone]
E-mail: [email protected]
Web site: www.symetrixaudio.com
POWER
THIS UNIT IS
XLR Pin 2 is HIGH.
be Balanced or Unbalanced.
Input and Output connections may
PIN 3 = RING = LOW
PIN 2 = TIP = HIGH
PIN 1 = SLEEVE = GROUND
TYPICAL CONNECTIONS:
REMOTE
BYPASS RIGHTRIGHT
OUTPUTS INPUTSOUTPUTS INPUTS
AC INPUT
LEFT
422
STEREO AGC/LEVELER
15 WATTS
LEFT
MANUFACTURED IN
LYNNWOOD, WA, U.S.A.
MAX
OUTPUT LEVEL
+12+60VU-6-12-18-24-30-36-42-48-54
0VU +6 [phone]-48-54
INPUT LEVEL
CLIP
BYP
SYSTEMPEAK LIMITTARGET LEVELRATIO
DETECTOR
AGC/LEVELER
422
STEREO
THRESHOLD (Vu) INPUT : OUTPUT OUTPUT LEVEL THRESHOLD (Vu)
+15
BYPASS
+5
-5
2.5 : 1
-15
INCREASE
5 : 1 DECREASE
BYPASS
-20
-45
LIMIT
IN
IN
BYPASS
BYPASS

422
2
Operator Safety Summary Chapter 2
Terms
Several notational conventions are used in this
manual. Some aragra hs may use Note, Caution,
or Warning as a heading. Certain ty efaces and
ca italization are used to identify certain words.
These are:
Note Identifies information that needs
extra em hasis. A Note generally
su lies extra information to hel
you to better use the 422.
Caution Identifies information that, if not
heeded, may cause damage to the
422 or other equipment in your
system.
Warning Identifies information that, if
ignored, may be hazardous to your
health or that of others.
CAPITALS Controls, switches or other markings
on the 422's chassis.
Boldface Strong em hasis.
Equipment Markings
AVIS:
NE PAS OUVRIR
Il ne se trouve a l’interieur aucune piece pourvant entre reparée l’usager.
SEE OWNERS MANUAL. VOIR CAHIER D’INSTRUCTIONS.
S’adresser a un reparateur compétent.
RISQUE DE CHOC ELECTRIQUE
No user serviceable parts inside. Refer servicing to qualified service personnel
.
CAUTION
WARNING:
TO REDUCE THE RISK OF FIRE OR
ELECTRIC SHOCK DO NOT EXPOSE
THIS EQUIPMENT TO RAIN OR MOISTURE
DO NOT OPEN
RISK OF ELECTRIC SHOCK
The lightning flash with arrowhead symbol within an
equilateral triangle is intended to alert the user of the
resence of uninsulated dangerous voltage within
the roduct s enclosure that may be of sufficient
magnitude to constitute a risk of electric shock to
ersons. The exclamation oint within an equilateral
triangle is intended to alert the user of the resence of
im ortant o erating and maintenance (servicing)
instructions in the literature accom anying the roduct
(i.e. this manual).
Caution To prevent electric shock, do not use the
polarized plug supplied with the unit with
any extension cord, receptacle, or other
outlet unless the lades can e fully
inserted.
Important Safety Instructions
Please read and kee these instructions. Heed
and follow all warnings and instructions.
Install in accordance with the manufacturer s
instructions.
Power Source This roduct is intended to
o erate from a ower source that does not a ly
more than 250V rms between the ower su ly
conductors or between either ower su ly
conductor and ground. A rotective ground
connection, by way of the grounding conductor
in the ower cord, is essential for safe o eration.
Grounding The chassis of this roduct is
grounded through the grounding conductor of the
ower cord. To avoid electric shock, lug the
ower cord into a ro erly wired rece tacle
before making any connections to the roduct. A
rotective ground connection, by way of the
grounding conductor in the ower cord, is
essential for safe o eration. Do not defeat the
safety purpose of the grounding plug. The
grounding lug has two blades and a third
grounding rong. The third rong is rovided for
your safety. When the rovided lug does not fit
your outlet, consult an electrician for re lacement
of the obsolete outlet.
Danger from oss of Ground If the rotective
ground connection is lost, all accessible conduc-
tive arts, including knobs and controls that may
a ear to be insulated, can render an electric
shock.
Proper Power Cord Use only the ower cord
and connector s ecified for the roduct and your
o erating locale. Use only a cord that is in good
condition. Protect the power cord from being
walked on or inched, articularly at lugs,
convenience rece tacles, and the oint where
they exit from the a aratus.
Proper Fuse The user accessible fuse is a art
of the IEC AC inlet connector. The fuseholder
acce ts 5 x 20mm diameter fuses. For 117VAC
o eration, the correct value is 0.5A, 250VAC,
standard. For 230VAC o eration, the correct
value is 0.25A, 250VAC, standard.
Operating ocation Do not operate this
equipment under any of the following condi-
tions: ex losive atmos heres, in wet locations,
in inclement weather, im ro er or unknown AC
mains voltage, or if im ro erly fused. Do not
install near any heat source such as radiators, heat
registers, stoves, or other a aratus (including
am lifiers) that roduce heat. Un lug this
a aratus during lightning storms or when
unused for long eriods of time.
Stay Out of the Box To avoid ersonal injury
(or worse), do not remove the roduct covers or
anels. Do not o erate the roduct without the
covers and anels ro erly installed. Only use
accessories s ecified by the manufacturer. Clean
only with a dam cloth.
User-serviceable parts There are no user
serviceable arts inside the 422. In case of
failure, refer all servicing to the factory. Servic-
ing is required when the 422 has been damaged
in any way, such as when a ower su ly cord or
lug is damaged, liquid has been s illed or
objects have fallen into the a aratus, the
a aratus has been ex osed to rain or moisture,
does not o erate normally, or has been dro ed.

422
3
Chapter 3
Front view (left side)
DETECTOR - Establishes an audio reference for the ur ose of discriminating between noise and
useful audio. The 422 will not attem t to a ly leveling (u ward gain increases) to signals that fall
below the detector threshold.
RATIO control - Sets the amount of downward com ression for signals exceeding the target level
as well as the amount of u ward leveling for signals below the target level.
TARGET EVE control - Establishes a nominal gain goal. For signals below the target level the
422 adds gain and boosts them u ward. Signals above the target level are reduced in gain (down-
ward towards the target).
PEAK IMIT control - Determines the level at which eak limiting gain reduction begins. Signals
exceeding this threshold will be reduced by a ratio of a roximately 15:1 (an increase of 15dB at
the in ut results in only 1 dB increase at the out ut).
BYPASS/IN button - Activates relays which route the 422 in ut signals directly from the in ut
connectors to the out ut connectors when in the BYPASS osition.
INPUT/OUTPUT EDs - Indicate the higher of either left or right channel calibrated in VU (volume
units). ( 0 VU=+4dBu).
Front view (right)
Front & Rear Panel Overview
TARGET LEVELRATIODETECTOR
AGC/LEVELER
422
STEREO
THRESHOLD (Vu) INPUT : OUTPUT OUTPUT LEVEL
2.5 : 1
INCREASE
5 : 1 DECREASE
BYPASS
-20
-45
LI
M
OUTPUT LEVEL
+12+60VU-6-12-18-24-30-36-42-48-54
0VU +6 [phone]-48-54
INPUT LEVEL
CLIP
BYP
SYSTEMPEAK LIMIT
THRESHOLD (Vu)
+15
BYPASS
+5
-5
-15
LIMIT
IN
IN
BYPASS
BYPASS

422
4
Rear panel view (left)
AC INPUT connector - Acce ts nominal AC ower sources of 117 volts or 230 volts.
REMOTE BYPASS connector - Provides for the control of the BYPASS/IN function via a remote
contact closure.
EFT INPUT connectors - Electronically balanced, bridging, line level in uts. XLR in 1 is ground,
in 2 is high, and in 3 is low. The 1/4" connector’s sleeve is ground, ring is low, and ti is high.
EFT OUTPUT connectors - Electronically balanced, low im edance, line level out uts. XLR in 1
is ground, in 2 is high, and in 3 is low. The 1/4" connector’s sleeve is ground, ring is low, and ti
is high.
RIGHT INPUT connectors - Electronically balanced, bridging, line level in uts. XLR in 1 is
ground, in 2 is high, and in 3 is low. The 1/4" connectors sleeve is ground, ring is low, and ti is
high.
RIGHT OUTPUT connectors - Electronically balanced, low im edance, line level out uts. XLR in
1 is ground, in 2 is high, and in 3 is low. The 1/4" connectors sleeve is ground, ring is low, and
ti is high.
Note For o timum immunity to noise and radio frequency interference we highly recommend
connecting the 422 to balanced equi ment, where ossible. If this is not ossible,
unbalanced connections are OK. Unbalanced connections via ti -sleeve (mono) 1/4" lugs
are easy to make via the 422's 1/4" in ut and out ut connectors.
Rear panel view (right)
POWER
THIS UNIT IS
REMOTE
BYPASS OUTPUTS INPUTS
AC INPUT
LEFT
422
STEREO AGC/LEVELER
15 WATTS
LEFT
MANUFACTURED IN
LYNNWOOD, WA, U.S.A.
MAX
XLR Pin 2 is HIGH.
be Balanced or Unbalanced.
Input and Output connections may
PIN 3 = RING = LOW
PIN 2 = TIP = HIGH
PIN 1 = SLEEVE = GROUND
TYPICAL CONNECTIONS:
RIGHTRIGHT
OUTPUTS INPUTS

422
5
InstallationChapter 4
Before you lug the 422 into a wall socket, carefully read the information in the following cha ter.
AC Line connection in countries outside of the European Community
A sticker on the right end of the unit indicates the nominal voltage setting for the unit as it left the
Symetrix factory. If this does not corres ond to the voltage setting for your locale then do not
attem t to a ly ower to the 422. Instead, return the unit to your local Symetrix distributor for
modification.
The 422 is shi ed from the Symetrix factory with a detachable AC ower cable (IEC standard)
included. De ending on the intended destination, the ower lug is either the US ty e (intended
for 117vac use), or the Euro lug ty e. If the ower cable s lug is not right for your locale, then
lease contact your local Symetrix distributor for the ro er cable.
Once you have determined that the 422 s o erating voltage matches that of your locale and you are
ready to begin, follow these ste s:
1 Plug the socket end of the ower cable into the recessed AC ower rece tacle on the back of
the 422.
2 Plug the other end of the ower cable into a three-hole grounded outlet or ower stri .
Warning The 422 is intended to be electrically grounded. It has been provided with a
three-wire grounding plug - a plug that has a third (grounding) pin. This plug
will fit only a grounded AC outlet. This is a safety feature. If you are unable to
insert the plug into the outlet, contact a licensed electrician to replace the outlet
with a properly grounded outlet. Do not defeat the purpose of the grounding
plug!
Mounting in an equipment rack
The 422 occu ies one rack s ace (1U) in a standard equi ment rack with a width of 19" (48.3cm),
a de th of 7.5"(19.1cm), and a height of 1.75"(4.45cm). Allow at least 4"(10.16cm) behind the unit
for the rotrusion of connectors. We recommend you take care not to mount the 422 next to
devices that emit large electromagnetic fields, such as audio ower am lifiers. To do so may
com romise the noise erformance of the 422. The 422 has been designed to conform to mechani-
cal guidelines as described in EIA Standard RS-310-C and IEC Recommendation 297.
Recommended audio cable wiring
For o timum system erformance we recommend that the 422 be connected to balanced signal
sources. If this is not ractical in your situation, then you may connect to unbalanced sources. The
diagram on the next age illustrates recommended cable wiring ractices.

422
6
Male 1/4" tip-ring-sleeve plug
Tip = high
Ring = low
Sleeve = ground
Male 1/4" tip-sleeve plug
Tip = high
Sleeve = ground
Male 1/4" tip-ring-sleeve plug
Tip = high
Ring = low
Sleeve = ground
Male 1/4" tip-sleeve plug
Tip = high
Sleeve = ground
Ring
Sleeve
Tip Ring
Sleeve
Tip
Sleeve
Tip
Sleeve
Tip
(Balanced)
(Balanced)
(Balanced)
(Unbalanced)
422 Output
Destination device input
Female XLR
Pin 1 = ground
Pin 2 = high
Pin 3 = low
Male XLR
Pin 1 = ground
Pin 2 = high
Pin 3 = low
2
2
3
3
1
1
Female XLR
Pin 1 = ground
Pin 2 = high
Pin 3 = low
2
3
1
Male 1/4" tip-ring-sleeve plug
Tip = high
Ring = low
Sleeve = ground
Ring
Sleeve
Tip
Male 1/4" tip-ring-sleeve plug
Tip = high
Ring = low
Sleeve = ground
Male 1/4" tip-ring-sleeve plug
Tip = high
Ring = low
Sleeve = ground
Male 1/4" tip-sleeve plug
Tip = high
Sleeve = ground
Male 1/4" tip-ring-sleeve plug
Tip = high
Ring = low
Sleeve = ground
Male 1/4" tip-sleeve plug
Tip = high
Sleeve = ground
Ring
Ring
Sleeve
Sleeve
Tip
Tip
Ring
Sleeve
Tip
Sleeve
Tip
Sleeve
Tip
Male XLR
Pin 1 = ground
Pin 2 = high
Pin 3 = low
2
3
1
Source device output
(Balanced)
(Balanced)
(Balanced)
(Unbalanced)
Female XLR
Pin 1 = ground
Pin 2 = high
Pin 3 = low
Male XLR
Pin 1 = ground
Pin 2 = high
Pin 3 = low
2
2
3
3
1
1
422 Input

422
7
OperationChapter 5
The TARGET EVE control
When setting u the 422, this is generally the control that you should adjust first. The TARGET
LEVEL control does just what the name im lies. It establishes the volume where you want it.
Technically, the control sets a threshold. Incoming signals that exceed this threshold are com-
ressed downward towards the threshold. Incoming signals below the threshold are ex anded
(leveled) u ward towards the threshold. The 422's out ut is a reduced dynamic range re lica of its
in ut, centered around the target level. As you adjust the TARGET LEVEL control, it s very easy to
see and hear the results. A quick glance at the OUTPUT level VU meter will show you the exact
effects of increasing or decreasing TARGET LEVEL.
The DETECTOR control
The DETECTOR control increases or decreases the sensitivity of the 422 to low level audio signals
and noise. As you turn this control counterclockwise, the 422 reaches down and increases the gain
of low level audio and/or noise. The o timum setting of this control is entirely de endent u on the
nature of the audio that the 422 is rocessing. For exam le, if the audio source is relatively clean
and quiet (like a CD), the osition of the DETECTOR may be noncritical. To greatly increase the
volume of the low level signals on the CD, try a full counterclockwise setting of the control (-45).
On the other hand, if you try the same extreme setting with a noisy cassette recording, you may not
find the results to be leasing. If you re rocessing a very noisy source, then turn the detector
control clockwise towards the -20 setting until the desired sound is achieved.
If you re unsure of where to osition the DETECTOR control, then start with it straight u in the
twelve o'clock osition. Weve found this to be a good com romise for un redictable audio
sources.
The RATIO control
The RATIO control is used to increase or decrease the degree of leveling. At high ratios, the
rogram density increase results in a more resent or u front sound. At low ratios, the 422
erforms subtle, yet effective, automatic gain riding. At a setting of 5:1 (maximum) the effect of
the 422 AGC/leveling rocess is very audible.
The o timum setting of this control is usually dictated by the articular ty e of material one is
rocessing, and the desired effect. For exam le, if the 422 is art of a foreground/background
music/ aging system in a high ambient noise environment, a higher ratio will roduce maximum
intelligibility. As art of a broadcast chain, where the rocess itself must be as subtle as ossible, a
2.5:1 or lower ratio is advisable.
If you re unsure of where to osition the ratio control, then we suggest you start in the twelve
o'clock osition and make u ward and downward adjustments from there as you listen and
evaluate the results.
The PEAK IMIT control
The PEAK LIMIT control sets an absolute ceiling threshold level to which the maximum out ut level
is limited. The control is calibrated in VU (volume units). The PEAK LIMITER is useful in any
a lication where it is desired to revent overload of subsequent system com onents. This may
include a lications such as high volume music systems in clubs and theatres, or transmission line
a lications such as AM/FM radio and television.
When the control is turned to its full clockwise rotation, the PEAK LIMITER is by assed. As the
control is rotated counterclockwise, the threshold is moved lower and the resultant limiting can be
observed as a reduction in overall out ut level on the OUTPUT LED meter.
The o timum setting for the PEAK LIMIT control is most often correlated directly to requirements of
downstream system com onents. If you’re unsure of where to set the control, then you may want to
try this: observe the OUTPUT level dis lay and note the average out ut level, then adjust the PEAK
LIMIT control 10-12dB above the average out ut level. Set this way, the eak limiter will rovide
rotection without over limiting the signal. The LIMIT LED should only come on occasionally. If it
stays on constantly then your are a lying too much limiting and should turn the PEAK LIMIT control

422
8
clockwise to reduce the amount of limiting. If you do not have a clearly identified need to eak
limit your signal, then we recommend that you turn the PEAK LIMIT control to the fully clockwise
BYPASS osition.
The SYSTEM BYPASS/IN button
The BYPASS/IN button laces the 422 in either BYPASS or IN (CIRCUIT) modes. In BYPASS mode the
incoming signals are directly routed (via relays) to the 422's out uts, thereby by assing any
internal circuitry. In BYPASS mode the front anel rotary controls have no effect on the o eration of
the 422. A red LED indicates BYPASS status, while a green LED indicates IN status.
The INPUT AND OUTPUT level meters
The INPUT and OUTPUT level meters are calibrated in VU (volume units). The meters read the
greater of either left or right channel signal levels. The meters give an indication of absolute signal
levels, and show the exact relationshi between in ut and out ut signals as a result of various
settings of the 422's controls.

422
9
SpecificationsChapter 6
Note The maximum operating ambient temperature is
25 degrees C.
The Automatic Gain Controller (AGC-Leveler) shall be a stereo model that reduces the dynamic
range of wide range, wideband audio signals and rovides eak limiting. The AGC shall occu y
one rack s ace (1U).
The AGC-Leveler shall be ca able of controlling audio signals ranging from -70dBu to +24dBu
and reducing their range by an in ut/out ut ratio of from 1:1 to 5:1. A target out ut level control
shall be rovided to shift the level of the out ut signal over a nominal ±20 dB range. The release
time of the AGC shall be controlled by the resence and nature of in ut signals.
The AGC-Leveler shall also contain an integral eak limiter having at least a 15:1 ratio and
adjustable threshold level. A green LED indicator shall be rovided to indicate eak limiter
activity. The eak limiter threshold shall determine the absolute maximum out ut am litude of the
AGC-Leveler regardless of other conditions.
The AGC-Leveler shall rovide identical eak res onding in ut and out ut level meters. These
meters shall be ca able of res onding to signals ranging from -48VU to +12VU (-50dBu to
+16dBu). An out ut cli ing indicator shall be rovided.
The in uts shall be active balanced bridging designs terminated with 3- in XLR (AES/IEC
standard wiring) female and 1/4" (ti -ring-sleeve) jacks.
The out uts shall be active balanced designs terminated with 3- in XLR (AES/IEC standard
wiring) male and 1/4"(ti -ring-sleeve) jacks.
Overall frequency res onse shall be 20Hz to 20kHz, ±1dB, measured at +4dBv out ut. There shall
be no more than 0.02% harmonic distortion measured under the following conditions: +4dBu
in ut, +4dBm out ut, BYPASS switch out, 1000Hz test frequency. Residual noise out ut shall be no
greater than -90dBu measured in a 20kHz noise bandwidth with an rms res onding meter.
When the unit is ino erative (either by loss of ower, or via the BYPASS switch), the in uts and
out uts shall be wired together. A REMOTE BYPASS facility shall be rovided whereby an external
contact closure shall force the AGC-Leveler into BYPASS mode.
The AGC-Leveler shall be ca able of o erating by means of its own built-in ower su ly con-
nected to 117V nominal AC (105 to 130V) 50/60 Hz and 230V nominal AC (207 to 253V AC).
The AGC-Leveler shall be a Symetrix, Incor orated model 422 Stereo AGC-Leveler.
422 Architects and Engineers Specifications
Input/Output
Inputs Stereo, Balanced Bridging or Unbalanced
Outputs Stereo, Balanced or Unbalanced
Input Connectors 1/4" TRS, XLR and RCA
OutputConnectors 1/4" TRS, XLR and RCA
Polarity Input: tip is high, ring is low, sleeve is ground
Output: tip is high, ring is low, sleeve is ground
Maximum Input Level +24 dBu
Maximum Output Level +22 dBu into 600 Ohms
Performance Data
Frequency Response 0 dB ±1 dB, 20 Hz - 20 kHz
THD+Noise .05%, 0 dBu in, 10 dB gain reduction, 1 kHz
Dynamic Range >110 dB
Crosstalk -60 dB, +20 dBu in, 20 Hz - 20 kHz
AGC DetectorRange -70 dBu to 0 dBu
Ratio 1:1 to 5:1
Target Level Range 30 dB
Limiter Threshold -15 dBu to +25 dBu
Limiter Ratio >15:1
Input Common ModeRejection 40 dB @ 1 kHz
Output Noise -90 dBu, broadband
Physical
Size (hwd) 1.72 x 19 x 5.5 inches, 4.37 x 48.26 x 13.97 centimeters
Shipping Weight 8 lbs (3.63kg)
Electrical
Power Requirements 117V nominal, 105 to 130V AC,
50 to 60 Hz, 12 watts
230V nominal, 207 to 255V AC, 50 Hz, 12 watts
422 Specifications

422
10
Troubleshooting Chapter 7
SYMPTOM PROBAB E CAUSE
There is no out ut signal Check the AC ower connections to the 422.
Check in ut and out ut cables and connections.
Determine that there really is a signal coming from the source
and that it is getting to the 422.
Distortion in the out ut signal Check the in ut signal. Is it overdriving the 422 s in ut?
Is the incoming signal already distorted? Listen u stream
from the 422 (or manually lace the unit in BYPASS mode) to
determine that you are feeding it a clean signal.
Buzz in the out ut
Check in ut and out ut connector wiring.
Check for ground loo s between interconnected system
equi ment.
Are all system com onents on the same AC ground?
Noise (hiss) Check in ut signal levels and in ut level control settings. The
in ut may be too low in level. If so, boost the signal from your
console or in ut source.
Is the in ut signal already noisy? Disconnect the in uts from
the 422 and listen for noise at the out ut. If the noise is gone,
then the roblem is rior to the 422.
The 422 doesn t ower u Consult a qualified service technician or the Symetrix factory.
or doesn t res ond ro erly.

422
11
Warranty & ServiceChapter 8
Warranty
Following are the terms and limitations of the Symetrix warranty.
Symetrix, Inc. expressly warrants to the original purchaser ( Buyer ), subject to the terms and conditions set forth
below, that the roduct will be free from defects in material and workmanship as a result of normal commercial use
for eighteen (18) months from the date of shipment.
Some Symetrix products contain embedded software and may also be accompanied by control software intended to
be run on a personal computer. Said software is specifically excluded from this warranty.
Symetrix's warranty obligation is limited to the repair, replacement, or refund at Symetrix's sole discretion, of the
part or parts of the roduct which may thus prove defective in materials or workmanship within one year from date
of purchase under normal use and which our examination discloses to our satisfaction to be thus defective,
provided that Buyer gives Symetrix prompt notice of its warranty claim and satisfactory proof thereof.
Symetrix will make every reasonable effort to ensure that parts are available to support the repair of our products
under warranty. In the event that a product or component part thereof becomes obsolete, unavailable or irreparable,
Symetrix reserves the right to refund a prorated portion of the purchase price in full satisfaction of all warranty
claims.
In order to serve you better we require that the Buyer shall, prior to shipping roduct to Symetrix for warranty
service, contact Symetrix and secure a Return Authorization Number that shall be included with the returned
roduct. This will facilitate our efforts to keep track of your roduct and process your warranty repair as quickly as
possible. Buyer will prepay all freight charges to ship the roduct to Symetrix for warranty inspection and service.
This warranty is subject to Symetrix's inspection of the roduct at its facilities and, upon Symetrix's request,
satisfactory proof of purchase (dated copy of original retail dealer s invoice.)
Symetrix reserves the right to effect repairs to the product with reconditioned components/parts. roducts once
repaired under warranty will be shipped to Buyer freight prepaid by Symetrix via United arcel Service (surface) or
any similar shipper, to any location designated by buyer within the Continental United States. At Buyer's request
and expense roduct will be returned via airfreight. Outside the continental United States, repaired or replaced
products will be returned freight collect.
THIS WARRANTY IS EX RESSLY IN LIEU OF ALL OTHER WARRANTIES EX RESS OR IM LIED, ARISING
BY LAW OR OTHERWISE (INCLUDING, WITHOUT LIMITATION ANY OBLIGATIONS OF THE SELLER WITH
RES ECT TO CONSEQUENTIAL DAMAGES) INCLUDING THE WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR USE AND OF ALL OTHER OBLIGATIONS OR LIABILITIES ON OUR ART, AND WE NEITHER
ASSUME, NOR AUTHORIZE ANY OTHER ERSON TO ASSUME FOR US, ANY OTHER LIABILITY IN CON-
NECTION WITH THE SALE OF THE RODUCT. THIS WARRANTY SHALL NOT A LY TO THIS RODUCT
OR ANY ART THERE OF WHICH HAS BEEN SUBJECT TO ACCIDENT, NEGLIGENCE, ALTERATION,
ABUSE, OR MISUSE. WE MAKE NO WARRANTY WHATSOEVER IN RES ECT TO ACCESSORIES OR ARTS
NOT SU LIED BY US. THE TERM ORIGINAL URCHASER, AS USED IN THIS WARRANTY SHALL BE
DEEMED TO MEAN THAT ERSON OR COM ANY THAT ORIGINALLY URCHASED THE RODUCT.
This Symetrix product has been designed and manufactured for use in professional/industrial systems and is not
intended for other usage. This warranty only applies to Buyers using the roduct in professional/industrial systems.
With respect to others, including but not limited to consumers for personal, family, or household use, Symetrix
expressly disclaims all warranties, including but not limited to warranties of merchantability and fitness for a
particular purpose and the express warranties as otherwise provided herein.
Symetrix reserves the right to modify the design or make additions to, or improvements to, its product lines without
making similar upgrades to roduct purchased by Buyer. Symetrix does not authorize any third party, including any
dealer or sales representative, to assume any liability, effect any repairs or modifications to the roduct, or make
any additional warranties or representation regarding the roduct or roduct information on behalf of Symetrix.
Symetrix's total liability on any claim, whether in contract, tort (including negligence) or otherwise arising out of,
connected with, or resulting from the manufacture, sale, delivery, resale, repair, replacement or use of roduct will
not exceed the purchase price of the roduct or any part thereof which gives rise to the claim. In no event will
Symetrix be liable for any incidental or consequential damages including but not limited to damage for lost revenue,
cost of capital, claims of customers for service interruptions or failure to supply, and costs and expenses incurred in
connection with labor, overhead, transportation, installation or removal of products or substitute facilities or supply
houses as a result of roduct failure.
This limited warranty gives Buyer certain rights. Buyer may have additional rights under applicable law.

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Servicing the 422
If you have determined that your 422 requires re air services and you live outside of the
United States, lease contact your local Symetrix dealer or distributor for instructions on how
to obtain service. If you reside in the U.S. then roceed as follows:
Before sending anything to Symetrix, contact our Customer Service De artment for a return
authorization (RA) number. The tele hone number is [phone] or email:
[email protected]
In-warranty Repairs
To get your 422 re aired under the terms of the warranty:
1. Call us for an RA number.
2. Pack the unit in its original ackaging materials.
3. Include your name, address, daytime tele hone number, and a brief
statement of the roblem.
4. Write the RA number on the outside of the box.
5. Shi the unit to Symetrix, freight re aid.
We do not accept freight collect shipments.
Re airs made in-warranty will cost you only one-way freight charges. We'll re ay the return
(surface) freight.
If you send us your roduct in substandard ackaging, we will charge you for factory shi ing
materials. If you dont have the factory ackaging materials, lease use an oversized carton,
wra the unit in a lastic bag, and surround it with bubble-wra . Pack the box full of
Styrofoam eanuts. Be sure there is enough clearance in the carton to rotect the rack ears
(you wouldn't believe how many units are returned with bent ears). We will return the unit in
Symetrix ackaging. Of course, if the re air is due to o erator error, arts and labor will be
charged. In any event, if there are charges for the re air costs, you will ay for the return
freight. All charges will be COD unless you have made other arrangements ( re aid, Visa or
Mastercard).
Out-of-warranty Repairs
If the warranty eriod has assed, you'll be billed for all necessary arts, labor, ackaging
materials, and freight charges. Please remember, you must call for an RA number before
sending the unit to Symetrix.

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Remote Bypass WiringAppendix A
For those installations that may require remote by assing of the 422's functions, a rear anel jack
has been rovided to acce t an external switch for this ur ose. The external switch should be a
high quality, industrial grade, single ole, double throw toggle switch. We highly recommend that
shielded wire be used to connect the switch to the 422 so as to minimize the ossibility of introduc-
ing any radio frequency interference into the 422. The external 1/4" audio lug should be of the
ti -sleeve ty e (often referred to as a mono lug). The following diagram illustrates recom-
mended wiring ractice.
The cable should be wired as shown above and as described below:
1. The ti of the 1/4" lug is soldered to one end of the signal wire of a coaxial cable.
2. One end of the shield of the coaxial cable is soldered to the sleeve of the 1/4" lug.
3. The other end of the signal wire is soldered to the common terminal of a single ole, double
throw switch.
4. The remaining shield is soldered to either of the remaining terminals of the switch (one
terminal remains unconnected).
User supplied remote bypass circuitry
Bypass
In (operate)

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Declaration of Conformity
Declaration of Conformity
We, Symetrix Incorporated,
6408 216th St. SW, Mountlake Terrace, Washington, USA,
declare under our sole res onsibility that the roduct:
422 Stereo AGC-Leveler
to which this declaration relates,
is in conformity with the following standards:
EN 60065
Safety requirements for mains operated electronic and related
apparatus for household and similar general use.
EN 50082-1
Electromagnetic compatibility - Generic immunity standard
Part 1: Residential, commercial, and light industry.
The technical construction file is maintained at:
Symetrix, Inc.
6408 216th St. SW
Mountlake Terrace, WA, 98043
USA
The authorized re resentative located within the Euro ean Community is:
World Marketing Associates
P.O. Box 100
St. Austell, Cornwall, PL26 6YU, U.K.
Date of issue: 18 January, 1995
Place of issue:Mountlake Terrace, Washington, USA
Authorized signature:
Dane Butcher, President, Symetrix Incorporated.
Appendix B

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422
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Symetrix, Inc.
6408 216th St. SW
Mountlake Terrace, WA, 98043
USA
Tel: [phone]
Fax: [phone]
Web site: www.symetrixaudio.com
Email: [email protected]