Shure AVC20 User manual

Owner's Manual
VIDEO / HI-FI SYSTEM EXPANDER
222 HARTREY AVENUE EVANSTON, ILLINOIS 60202-3696U.S.A TELEPHONE [phone] CABLE SHUREMICRO

NOTICE
The AVC20 offers the choice of three different types
of surround-sound effects: Dolby Surround, Spatial
Surround,or Concert Surround.
The AVC20 is equippedwith Four Power amplifiers.
The AVC20 allows central control of most video equip-
ment.
4 types of easy to operate volume balancecontrols.
The AVC20 is equippedwith
a sound memory circuit.
The Surround Indicator can be switched on or off.
The AVC20 can be used as
a high output stereo amp-
lifier when inthe Balanced Transformerless (BTL) mode.
TABLE OF CONTENTS
..........................................
Special features 2
.....................................
Surround-soundeffects 3
.....................................
Installingthe glass door 3
.........................................
Locatingspeakers 4
.....................................
Connectionof speakers 5
......................
Function names and operations - Front panel
6
......................
Function names and operations - Rear panel.
8
................................
Volume - Balance control ; .. 10
................................
Use of wireless remotecontrol 11
..............................
Use of the image enhancer switch 14
............................................
Applications 15
Exampleof use with avariety of different equipment
..................................
(Monophonicvideo deck) 20
....................................
(STEREOvideo deck) 21
......................................
(Twovideo decks) 22
............................
(Videodeck and video disc player) 24
.......................
(TV equippedwith video input terminal)
26
....................................
(Overallconnections) 28
.........................................
Cautions on usage 30
........................................
Troubleshooting.. 31
...........................................
Specifications 31
This equipment generates and uses radio fre.
quency energy and if not installed and 1
properly, that is, in strict accordance wi
manufacturer's instructions, may cause interler-
ence to radio and television reception. It has
been type tested and found to comply \n 'je
limits for Class €4 computing device in jr.
dance with the specifications in Subpart J of
Part 15 of
FCC Rules, which are designed to
provide reasonable protection against such
interference in a residential installation. How-
ever, there is no guarantee that interference
will not occur ina particular installation. If this
equipment does cause interference to radio or
television reception, which can
be determined
by turning the equipment off and on, the user
is encouraged to try to correct the interference
by one or more of the following measures
- reorient the receiving antenna
- relocate the equipment with respect to the
receiver
- move the equipment away from the receiver
- plug the equipment into a different outlet
so that ecluipment and receiver are on dif-
ferent branch circuits.
If necessary, the user should consult the dealer
or an experienced radioltelevision technician
for additional suggestions. The user may find
the following booklet prepared by the Federal
CommuincationsCommission helpful:
"How to Identify and Resolve Radio-TV inter-
ference Problems"
"This booklet is available frorr the
US Govern-
ment Printing Office. Washington.
D.C., ' ',
Stock No. 004-000-00345-4"
Caution: To prevent electric shock do not use
this (polarized) plug with an extension cord.
receptacle or other outlet unless the blades can
be fully inserted to prevent bladeexposure.
Attention: Pour prBvenir les chocs Blectriques ne
pas utiliser cette fiche polaris6e avec un prolon-
gateur, une prise de courant ou une autre sortie
de courant, sauf si les lames peuvent Btre ins6rBes
a fond sans en laisser aucune partie a dbcouven.
RISK OF ELECTRIC SHOCK
Amn
Caution: To reduce the risk of electric
shock, do not remove cover (or back).
No user serviceable parts inside.
Refer servicing to qualified service
personnel.
WARNING: TO PREVENT FIRE OR SHOCK HAZARD,
DO NOT EXPOSE
THIS APPLIANCE TO RAIN OR MOISTURE
The lightningflash with arrowhead symbol, within an equilateral
triangle, is intendedto alert the user to the presence of uninsulated
"dangerous voltage" within the product's enclosurethat may
be of
sufficient magnitudeto constitute a risk of electricshock to persons.
m
The exclamation point within an equilateraltriangle is intendedto
alert the user tothe presence of important operating and maintenance
(servicing)instructionsinthe literatureaccompanying the applianw

SURROUND-SOUND EFFECTS
Surround-sound
The AVC20 is equipped with three types of surround
processors which provide
a sense of presence and expan-
sion.
4 Every day, we are exposed to sounds coming from our
) surroundings. Some sounds reach our ears directly from
the source, some indirectly reflected off of walls or the
ceiling. Sounds of voices reach us from behind, sounds
of cars reach us from the side. Sounds coming from all
around us are called "surround-sounds".
In order to recreate with as much precision as possible,
that special sound heard in movie theaters, speakers are
placed both in front of and behind the listeners. The
reason that sound from the television inour homes
is so
different from the sound in movie theaters is because
sound from a television only comes from in front of
the viewer. With a surround system, the spatial infor-
mation encoded in a film's sound track will be repro-
duced in the home listeningarea.
The sound from a TV equipped with asingle speaker (or
two speakers with stereo televisions) sounds very dif-
ferent from the actual, "live" sound.
The AVC20 is equipped with three types of surround
processors to recreate that sense of presence and let you
enjoy surround-sound in the privacy of your own home.
Surround Processors
= DOLBY SURROUND*
Provides the optimal sound when watching recent movies,
especially those encoded with the DOLBY SURROUND
or DOLBY STEREO process. The front speakers provide
the normal stereo effect, while the rear speakers reproduce
the surround signals. This position provides excellent
results when watching television programs, video soft-
ware, video discs, or videotapes of stereo television broad-
casts.
CONCERT SURROUND
This provides the best results when watching old movies
or video recordings of concerts. The front speakers provide
the normal stereo effect, while the rear speakers provide
reverberation like that heard in concert halls. The reverbe-
ration time can be adjusted using the CONCERT
SURROUND Control.
SPATIAL SURROUND
Use this when watching livesports games to reproduce that
stadium feeling.
*Manufactured under license from Dolby Laboratories Licensing
Corporation. Additionally licensed under one or more of the
following patents:
U.S. numbers 3,632,886, 3,746,792, ar~d
3,959,590; Canada numbers 1.004.603 and 1.037.877 "Dolb~"
and the double-D symbol are trademarks of Dolby Laborator~es
L~cens~ngCorporat~on.
S STALLING THE GLASS DOOR

LOCATING SPEAKERS
Speaker locationwill depend ineach case on the size and
shape of the specific room in which the Home Theater
System is installed. The diagrams below may be used as a
general guide to speaker placement in rooms of various
shapes. To avoid interference with the tv picture, speakers
without special magnetic shielding should ordinarily be
more than 0.6m
(2 ft) from the screen. In each case, it is
best to consult the tv and loudspeaker manufacturers.
When a Center speaker is employed (See page
18). it
is most conveniently mounted above or below the screen,
but always as close to the screen centerline
as possible.
Because very low frequencies are nondirectional in
-
room, a subwoofer (See page 8) can usually be loca
,!
almost anywhere convenient in the room. However, de-
pending on room acoustics and the particular subwoofer,
some locations may be clearly superior to others. Consult
the subwoofer manufacturerfor specifics.
LOCATING SPEAKERS

CONNECTION OF SPEAKERS
Connectionof 4 Speakers
OPERATE SWITCH
+I
MONO OUT
I I
Normally this switch is SPEAKER AC OUTLET
Monophonic Output kept to the left (seen OUTPUT (SWITCHED)
Terminals from behind). TERMINALS
There is one set of four speaker output terminals. Use speakers with an impedanceof 8 to 16 ohms.
Connectionof Speaker Cables
Normal Speaker Connection
1. If the bare speaker wire is too short, strip off
the vinyl and make the exposed wires the
same length. lomm [318'n1
*F
EXAMPLE: With a speaker terminal on the
bottom side.
2. Press down the lever and insert the cord. Use a
"+" terminal for the + side ofthe speaker and
Remove your finger from the lever, and pull a
"-" terminal for the - side.
on the cord to be sure that
it is properly con-
3. Raise the lever.
nected. Be sure that the wire does not stick out
Put the Operation Switch in the
I NORMAL 1 from the cord and come into contact with
position. wire of another cord, as this may damage the
equipment.

FUNCTION NAMES AND OPERATIONS-FRONT PANEL
Function Names and Operations
@ Power Switch (POWER)
Use this switch to turn the power of the AVC20
on and off. After turning on, allow approximately
4 seconds to pass before using. During this time,
the FULL MUTE indicator on the concen-
trated indicator panel will flash, indicating that the
set is in the stand-bymode.
@ ConcentratedIndicator Panel
lndicators light up according to the operations
performedon the AVC2O.
@ SURROUND INDICATOR
Three red LEDs are displayed, depending on
the level at the AVMO speaker outputs.
Front Left Channel Front
Right Channel
Rear Left Channel
Rear Right Channel
@ REMOTE SENSOR
This is the window used for receiving the signal
from the suppliedwireless remote control unit.
BYPASS Use this position when you wish to
obtain stereo sound without any
surround effect.
Sound is produced only from the two
front speakers.
@ SYNTHETIC STEREO
Use this switch to obtain simulated
stereo sound from monophonic signals.
Use the SYNTHETIC STEREO vol-
ume control located insidethe control
panel door to adjust the stereo effect.
This function can also be used to expand a
stereo source.
@ CONCERT
SURROUND
This is the best position for viewing
@ Volume and BalanceControls
(For details, refer to page 10)
televised concerts or old movies.
Use the CONCERT SURROUND
@ InputSelector Switches and lndicators volume control located insidethe con-
(AUDIOIVIDEO SELECTOR) trol panel door to adjust the reverbera-
Use these switches to select the program source.
When the WE] switch is pressed, the
@ SPATIAL time.
.. SURROUND
sound source is switched to the component
I
This is the best position for viewing
connected to the TAPE input terminals while sports or music programs.
the video source
is provided by the A-V INPUT
whose selector switch
is pressed.
(For details, refer to page
18)

DOLBY This is the best position for viewing
SURROUND movies.
0 The AVC20 is equipped with the
proper Dolby Surround decoder for
use especiallywith video software con-
taining the DOLBY SURROUND
mark 00 ,,,,,,~ ,,~,,,,,, ,,( '" or movies inwhich the DOLBY
STEREO
rnark~OImre*m~mI'"appears at the end.
The Dolby Surround system is manufactured under
licence from Dolby Laboratories Licencing Corporation.
Refer topage 3 for moredetailed information.
@ SurroundIndicator Switch
(SURROUND INDICATOR)
Use this switch to turn the SURROUND
INDICATOR on or off.
Press once to turn the SURROUND INDICA-
TOR off if
it is distracting.
@ NOISE Filter Switch (NOISE FILTER)
This filter reduces the hissing noise
produced when viewing old movies for
1 example.
MONO INPUT
Depress when using a monophonic video deck.
The STEREO indicator will turn off.
@ FULL MUTE
Depressto cut off sound momentarily.
When dep~essed,the indicator will light.
Press again to return tothe original volume.
@ Volume Reset Switch (VOLUME RESET)
Use this to make the volume from each speaker
equal.
As the volume will be low when this is done,
use the volume switches
@ to readjust the
balance.
@ Image Enhancer Switch (IMAGE ENHANCER)
Use this switch to make the contours of the
pictureclearer.
0 3dB
0 6dB
0 OFF
*
As the image enhancer makes all details of the
picture clearer, small white spots on the screen
may also stand out, thus making the picture
actually harder to see. If this is the case, turn
the function OFF.
@$ Synthetic StereoControl (SYNTHETIC STEREO)
Use this control to adjust the effect when the
SYNTHETIC STEREO switch
@ is turned on.
Expansion becomes greater when turned clock-
wise, and lower when turned counterclock-
wise.
@ ConcertSurroundControl (CONCERTSURROUND)
Use this control to adjust the effect when the
CONCERT SURROUNDbutton
@ is depressed.
The reverberation time is increased when
turned clockwise.
@ Input Balance Control (INPUT BALANCE)
Use this to balance the left and right channels
of the input source.
@ INPUTVOLUME
Use this control toset the maximum volume.
(Referto page 10 for details.)
@ Tone Control
Treble and bass tones can be controlled for both
the front and rear speakers.
Use the FRONT control to adjust the tone of
the front speakers, and the REAR control for
the rear speakers.
Use the TREBLE and BASS controls to adjust
treble or bass.
Turn clockwise to increase the effect, or count-
erclockwiseto decrease.

FUNCTION NAMES AND OPERATIONS-REAR PANEL
FunctionNames and Operations
@ A-V INPUT 1 Input/Output Terminals
@ A-V INPUT 2 InputIOutputTerminals
A-V INPUT
@ and @ Input/Output Terminals
are used for connection of components on which
recordingis possible, such
as a video deck.
@ A-V INPUT 3 lnputTerminals
A-V
INPUT@ lnput Terminals are used for con-
nection of components for which only playback
is possible, such as video disc playerscompactdisc
players, or television tuners.
@ PHONO lnputTerminals
PHONO lnput Terminals are used for connection
of aPhono Turntable without preamp.
NOTE: Selected input signals (including PHONO
and TAPE) appear at output jacks of A-V INPUT
1, A-V INPUT2 and TAPE.
0 Monitor Output Terminals (MONITOR OUT)
These are used for connection to video input
terminals of color monito,rs or televisions
equippedwith video input terminals.
There are two independent output terminals,
making possible the connection to two com-
ponents.
@ Tape Input/OutputTerminals (TAPE INIOUT)
Connect an audio cassette deck or the like to
these terminals.
(For details, refer to page 18)
@ These are front speaker preamplifier output and
mainamplifier input terminals.
@ These are rear speaker preamplifier output and
mainamplifier inputterminals.
Use these for connection of an equalizer or
signal processor or of a pre-amplifier or main
amplifier other than those of the AVC20.
Usually, use the AVC20 with the pre-amplifier
output terminals connected to the main
amplifier input terminals with the supplied
U-
shapedconnectingpin.
The AVC20 can also be used in the BTL mode
or
as a surround processor. For details, refer to
Pages
15 and 17.
@ Monophonicoutput Terminal
MONO OUT A,
B
Use these outputs for connection to a Sub-
woofer or center channel amplifier and speaker
(A sub-woofer will transduce only low-frequ-
ency signals, a full-rangespeaker will handle the
completeaudio spectrum.)
The output level is approximately 1 V at arated
input. Match with the input sensitivity of the
speaker or other componentto be connected.
The output signal of terminals
@,) is a mixture
of the front left and right channels. When the
volume of the front speakers is high, the MONO
output level also increases.This can be used as a
center channel output.
(For details, referto page
18).

@ OperationSelectorSwitch
Use this switch to select NORMAL or Balanced
Transformerless(BTL)operation.
NORMAL Operation
0 Use this position for independent operation
of the four power amplifiers.
0 This is the position in which the AVC20 is
normall y used.
0 In this position, the AVC20's output is
30W x
4.
BTLOperation
0 Use this position to use the AVC20 as a
stereo amplifier, with the four power ampli-
fiers combinedin groupsof two.
0 In this position, the AVC20's output is 60W
x 2.
@ Power Cord
Plugthis into an ac wall outlet. 120Vac 60Hz.
@ Supplementary Power Outlets (AC OUTLETS)
SWITCHED
This outlet operates only when the AVC20
power is on.
Use this outlet to plug in equipment with a
maximum power consumptionof 100W.
Use this outlet for example for a self-powered
subwoofer.
@ Supplementary Power Outlets (ACOUTLETS)
UNSWITCHED
These outlets can be used regardlessof whether
the AVC20 power is on or not.
Use these outlets to plug in equipment with a
maximum power consumptionof 100W.
CAUTION
TURN OFF
AVC2O POWER BEFORE
OPERATING THIS SWITCH.
(For details, refer to page 15)
@ Speaker ConnectionTerminals
Use these toconnect speakers.
(Refer to page 5 for details.)
WARNING
Power Consumptionof Outlets
Never use the AC OUTLETS with equipment
which consumes more power than is indicated
on the panel (for example, toasters or hair
dryers). This could damage the equipment or
result inafire.

VOLUME-BALANCE CONTROL
The AVC20 is equippedwith 4 built-inpower amplifiers. The volume of each of these can be controlledseparately.
Volume Control
m
Press the upper side to simultaneously increase the volume of all four speakers.
Press the lower side to simultaneously decrease the volume of all four speakers.
IvoLuME
Volume increases faster than it decreases.
Balance Control
FR FL: lncreases the volume of the front left speaker.
FR: lncreasesthe volume of the front right speaker.
RL: lncreases the volume of the rear left speaker.
RR: Increases the volume of the rear right speaker.
FRONT: Causes the surround image to slowly travel towards the front.
REAR: Causes the surround image to slowly travel towards the rear.
RL
,, LEFT: Causes the surround image to slowly travel towards the left.
RIGHT: Causes the surround image to slowly travel towards the right.
When the volume of one of the four speakers reaches
the maximum level, the indicator flashes. When
the volume of one of the four speakers reaches the
minimum level, the indicator flashes.
This mark lights.
Dolby Surround and lnput Volume
The output level on some VHD video disc playersor laser disc players is quite high. When
this is the case, DOLBY SURROUND sound may be distorted. Should this happen, lower
the INPUT VOLUME. INPUT
VOLUME
lnput Volume
The lnput Volume control locatedbehind the control Adjusting the lnput Volume
panel door is usedto set the maximumvolume so
@ First set the INPUT VOLUME control to the mini-
that the volume of none of the speakers exceeds
a
mum. (Number @ inside the control panel door)
certain level.
@ Use the Volume up control and set the AVC20
volume to the maximum (the If_l indicator will
flash),then bring
it down 5 steps.
(Pressthe Volume down button
5 shorttimes)
@ Next gradually increase the lnput Volume until a
comfortable listening level is reached.
This is described by the following diagram.
Greatest volume which
w
LIMIT
This mark lights.
.fin
Volume you most frequently use.
+.-
can be produced by
the AVCZO
+------- Greatest volume set by
the INPUT
VOLUME
control.
- k4i.i-m volume -
LOWER
no sound is produced.