channel
rs
heard,
i.e..
shiltrng the sonrc
image to the right.
Rotation
lo the etl shilts
the
sonic
image toward the
left
speaker.
ldeallv
the detented
center
Dosition
of lhe BALANCE
control wr I
be
the normal setting. Bul several common
circumstances
may
cause unequatbaiance.
requiring a
compensalory ofl-center
BALANCE setting to
restore
the
most unrform
spread
ol stereo
sound
belween the
speakers
These
include
unequal
o!tput from the two channels of the
phono
carlridge. diflering acoustica environmenls
around the
two speakers. or simply
a listening
posilion
which
is
closer
to
one
speaker than to the olher. Adjust the
BALANCE
conlrol
lo
produce
a naturai spread
of
sound
across the
space between lhe speakers
with
any
monopho-
nic sound
(such
as
a
radio
announcer
s
vorce)
appearing
as a
phantom
image cenlered midway between them.
6. AUXi TUNER/PHONO.
These three bultons. and the
adjacenl TAPE
button,
selecl the
signai
source to be heard.
When lhe AUX.TUNEB, or PHONO
input rs
selecied, the
corresponding input srgnal
is
fed to the amp ilier s circuits
and also to lhe RECOFO
outpul
jacks
lor recording.
7. TAPE.
When thrs
button is
disengaged
(oul).
the input
signal
chosen
by lhe SELECTOF switch
(aux. phono,
tune4
is led to
the controls and
to
the
power
amplilier lor
lislening.
When lhe
TAPE button
is
engaged,
the outpul
signal
from
a tape recorder
(or
any signal
processor
connecled lo lhe
rear-panel PLAY
jacks)
rs
heard.
The
srgnal
to be
recorded
on tape
rs chosen
exclusrve
y
by the SELECTOF switch. and is
not
atfecled by the
VOLUME
or
anv other control.
When
you
are
making
a tape
recording,
engaging
the
TAPE
switch enables
you
1o hear the signa as
it
passes
through lhe tape
machine
s electronics
and
recording-
eve
controJs.
However. engagrng
and
disengagrng the
TAPE
bulton
may
slightly
altef lhe
srgna
levels
led
out
lo a tape
recorderi
therelore
the butlon
shou
d be
kept
engaged
during the
entire
duration
ol a
recording.
With
a
three-head
recorder
equipped
for
ofllhe'tape
monitoring.
the TAPE swrlch
permits you
to hear
the
p
ay-
back srgnal
lrom
the tape
rmmediately
aiter lhe
recording
s
made. In
order
to check
rts
quality
In thrs
case use the
lape
so!rce swrlch on the
recorder
lor
swrlching between
the
original
and recorded
srgnal.
ll
you
have connected a signal
processor
such as
a
graphic
equalizer or
dynamic-range expander lo the
FECORD'PLAY
jacks.
the TAPE
buiton
musl
be depressed
in
order to hear the eifects of lhe
processor
Norma
ly the
processor
will
have
its own
FIECORD PLAY
Jacks
and
tape
monitor
swilch
lor use
wrlh
a lape recorder
8.
MONO. Engaging this button
comblnes
the
two stereo
channels
together
to
produce
monophonic
sound,
minimlz'
ing vertical rumble and surface noise when lislening to old
monophonic recordings.
The
button must be
OUT
lor normal
stereo
listening.
9. LOUDNESS.
Pressrng this butlon engages a
"loudness
comoensalron clrcurl
whrch, al low.to-medium
settings of
the Volume
contro, boosls the bass and
treble
response
of
the
amplilier.
This is to
compensate
for
the
human ear's
reduced
sensilivity
to
lowjrequency sounds
at
low loudness levels,
and
lor the
'masking
ot high'
lrequency
delails by environmental norse The LOUDNESS
lunction
should
be drsengaged
when
you
are
listenrng
lo
music at
life-iri(e
volurne ievels
And
at
low leveis a more
accurate.
if less
convenienl.
loudness
compensalion
rray
be obtained
by
boosling the Bass
control
10. VOLUME. Adlusls the overal loudness
ol
lhe
sound,
in
conjunclion
wrth
the
Audio Mulrng
bullon.
The
contro is
designed
for accurate
trackrng
oi
lhe lwo channels, so that
lhe
stereo
balance wil not
shrft
as
the
VOLUME control
setlrng
is varied.
'11.
LED POWER METER.
Thrs row
ol
lve
LEDs
con-
tinually indicates the
peak
power
leve
wh ch the amp rfier
is delivering to
the
loudspeakers. The circu t
monitors
both
channels and
displays
the
higher
output al each
Instant.
The
calibrated
level ranges lrom l wat1
lo 35
watts
rnlo
an B-ohm
impedance, wrth
a
4-ohm rmpedance
the
nomrnai
power
is lwice the rndicated vaiue, so rhe
LE0s
.ange
lfom
2 to 70 watls
In addilron to
providing genera
inforrrrat on on
power
levels.
the LED
Power meler also te
ls
you
when
you
should
be using
the SoJl
Clipping circuit
ll
you
find thal on
y
the
tirst
two or
three
LEDs ever
illumrnate when
ycu
are
p
ayrng
musrc, then
you
may leave the
SoJl C
ipping sw tched
OFF
Bul whenever
you
fino
that
you
are
causrng
ali
|ve
LEOs
to il
uminate
even
rf only
momentafl
y
dur
n9 the
hrghesl
mlsical
peaks,
then
you
should
switch
ON
lhe Solt
C
rpp ng
on lhe
rear
panel
in order to
mlnrmize
any
harshness
or
dislorlion
which
would occur when the amo
ifier rs over-
dnven beyond
its
rated
power
A Note on Protection. Because lhe 3020A
sounds
so
c
ean
and
musrcal
when driven beyond its
nomrna
power
rating and
when
used to drive
low-rmpedance loudspeakers,
you
may be
tempted
10 stress
it beyond its
design
capac ly.
For example
rt
can sale
y
and cleanly drive a
2-ohm
imped-
ance
with wide-range
musical srgnals whose
peak
level
rs
several
tens
of
walts and whose
average
evel
is much
lower;
bul
rt will
overheal
it
called upon
10
del,ver
hrgh
power
continuouslv
nlo
a low
impedance. There are thermostatrc
crrcuit
breakers
In
the output
stage. whrch are acl
vated I
the oulput
transrslors
become
dangero!sly
hot. When
this
occurs
in either
channe
the output
slage
automatrcally shuts
down
io
protecl
rlsell.
Thus il one
or both channe
s
ol sound
go
srlent while
lhe
fronl-panel
LEDs
remain
rllumrnated
(indicalrng
lhal lhe
marn
power-supply
luses
and
operatrng vo lages are still
normal), the thermostatic
circurt
breakers may
have
been
activated
To
resume
operation
srmply
lurn down
the volume
and
wait a minute
or
so tor the outpul stage
to cool
and
the
circuit breakers 10 aulomatrca
ly re'sel. lf the
proleclrve
circuit breakers
inlerrupt the sound
repeatedly,
examine the
speaker
wiring lor
a
possible
loose
strand
of
wrre
causing a
partial
shorl-crrcuit, or
reduce the
volume
level sIghliy.
Tl'e
toht4rnq
fash \rlh
arrowhead
wrlqr-
ar
eqL,latera
/\
tt
"ngte
,s
nlenoed
ro alerr l'e -ser or l_p
presence
ol
/fif
u-ris-tateo oangF'ous
voltaqe wrl'r-
lFe
prooLcl
s encro
/ll
sure thal
may
be ol sullrcrenl
magnrtude
to constrlule a
-. risk ot electnc shock to oersons.
The erclar'la!,oF
po
nt wrth.
an
equ
lale.al
'ranqle
rs
r.lenoeo
n
to drerl
lhe -se; of
the
presence
ot
r.nportant
ooe'anng a'rd
4'
,t""""ce,servc
ng'
nsr'-clrons,n lhe lrle aru'e
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