Aux Tuner/Phono; Tape; Mono; Loudness - NAD 3020A Instructions For Installation And Operation Manual

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.
W h e n l h e A U X . T U N E B , o r P H O N O i n p u t r s s e l e c i e d , t h e
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
V O L U M E o r a n v o t h e r c o n t r o l .
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
m a d e . I n o r d e r t o c h e c k r t s q u a l i t y I n t h r s c a s e u s e t h e l a p e
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
l h e s t e r e o b a l a n c e w i l n o t s h r f t a s t h e V O L U M E c o n t r o l
setlrng is varied.
' 1 1 . L E D P O W E R M E T E R . T h r s r o w
o l l v e L E D s c o n -
tinually indicates the peak power leve wh ch the amp rfier
is delivering to the loudspeakers. The circu t monitors both
c h a n n e l s a n d d i s p l a y s t h e h i g h e r o u t p u t a l e a c h I n s t a n t . T h e
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
l e v e l s . t h e L E D P o w e r m e l e r a l s o t e l s y o u w h e n y o u s h o u l d
b e u s i n g t h e S o J l C l i p p i n g c i r c u i t l l y o u f i n d t h a l o n y t h e
t i r s t t w o o r t h r e e L E D s e v e r i l l u m r n a t e w h e n y c u a r e p a y r n g
musrc, then you may leave the SoJl C ipping sw tched OFF
Bul whenever you fino that you are causrng ali |ve LEOs
t o i l u m i n a t e e v e n r f o n l y m o m e n t a f l y d u r n 9 t h e h r g h e s l
m l s i c a l p e a k s , t h e n y o u s h o u l d s w i t c h O N l h e S o l t C r p p n g
o n l h e r e a r p a n e l i n o r d e r t o m l n r m i z e a n y h a r s h n e s s o r
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