Pioneer SA 708 Owners Manual

Page 1

STEREO AMPLIFIER

GDPIONEEIT

A-7DB

HA,HR
S,S/G

OPERATING INSTRUCTIONS

The specifications of this model differ according to the

shipment destination.

0 For UK. and Australia (HR stamped on packing case):
Power line voltage is 240 volts. A DIN socket is provided
on the rear panel,

0 For mainland Europe (HA stamped on packing use):
Power line voltage is 220 volts. AC convenience outlets
are provided on the rear panel, and a DIN socket is pro-
vided on the rear panel.

a For destinations excluding above (5 or 5/6 stamped on
packing case): A 4-point (llOV/12OV/220V/240V) volt-
age selector switch is provided on the rear panel, and AC
convenience outlets are provided on the rear panel.

NOTE:

Models for the UK. and Australia (HR) and mainland
Europe (HA) have their power line voltages set in accord-
ance with their destination before they are shipped from
the factory. The voltage which has thus been set is indi-
cated on the rear panel ofthe main unit.

Before switching on the power, make absolutely sure that
the voltage tallies with the value used in your area. If it
does not tally or if you move to another area with a dif-
ferent voltage (such from 220Vto 240V) or vice versa, get
in touch with your nearest authorized Pioneer Service
Center or Service Station or, alternatively, call for a quali-
fied electrician to set the voltage properly.

(IMPORTANT

To prevent electric shock, do not remove cover. No user
serviceable parts inside, refer servicing to qualified serv-
ice personnel.

Always disconnect all the equipment from the mains
supply when disconnecting the signal leads. The power
cord should be connected last, make sure that the power
switch is off. First, insert the female appliance connector
of the mains cord into the AC INLET, then plug the
cord to the wall socket. Be sure that the appliance con-
nector is fully inserted into the AC INLET.

Unplug the set from the wall socket when it is not to be
used for an extended period of time.

WARNING
THIS APPARATUS MUST BE EARTHED.

FOR YOUR SAFETY

1. Insert this plug only into effectively earthed three-pin
plug-socket outlet.

2. If any doubt exists regarding the earthing, consult a
qualified electrician.

3. Extension cords, if used, must be three-core correctly
wired.

FOR USE IN UNITED KINGDOM AND
AUSTRALIA

CAUTION 240V: Mains supply voltage is facto-
ry adjusted at 240V.

FOR USE IN UNITED KINGDOM
The wires in this mains lead are coloured in accordance
with the following code:

Greenond-Yellow: Earth

Blue: Neutral

Brown: Live
As the colours of the wires in the mains lead of this ap-
paratus may not correspond with the coloured marking
identifying the terminals in your plug proceed as fol-
lows.
The wire which is coloured greenond-yellow must be
connected to the terminal which is marked with the let-
ter E or with the safety earth symbol 4:- or coloured
green or green-and-yellow.
The wire which is coloured blue must be connected to
the terminal which is marked with the letterN or colour-
ed black.
The wire which is coloured brown must be connected to
the terminal which is marked with the letter L or colour~
ed red. J

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Page 2

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coyTE

Features .............................

Stereo System Composition .............. 3
Installation Precautions .................. 3
Rear Panel Facilities .................... 4
Connections .......................... 5
Front Panel Facilities ................... 8

lglgtions ........................... 10
Using the Tape Decks .................. 11
Conditions Frequently Mistaken for

Malfunctions ....................... 12
Specifications ................... Insertion
Schematic Diagram ............... Insertion

FEATURES

DC Power Amplifier with High S/N and Low Dis-
tortion

This is a DC configuration power amplifier which uses
superlinear transistors with excellent highrange switching
characteristics for the power transistors. The result is a

Continuous Power Output of 65 watts per
channel, min., at 8 ohms from 20 Hertz to
20,000 Hertz with no more than 0.02%
total harmonic distortion or 65 watts per
channel at 4 ohms from 20 Hertz to 20,000
Hertz with no more than 0.03% total
harmonic distortion.

The power amplifier circuit board features a heat sink
partition to separate the small-signal class A amplifier sec-
tion and the output stage class B amplifier section and
power supplies. This prevents interference between the
small-signal and large-signal sections. Furthermore, the heat
sink is lightweight and has a T-shaped skyve construction
for an effective heat dissipation capability. This feature
keeps the rise in the temperature down and it ensures that a
high-quality sound is provided.

Equalizer Amplifier with a High S/N and Low Dis-
torsion

The 3-stage directcoupling with three low-noise tran-
sistors is a design which brings out the best in the final-stage
emitter follower equalizer amplifier. All the various com-
ponents that are used for the equalizer elements help pro-
vide a PHONO signal-to-noise ratio of 86dB (IHF-A), an
RIAA deviation of 10.2dB (20Hz to 20,000Hz), and a
phono overload level of 200mV (1 kHz, T.H.D 0.01%) for
the high-fidelity recreation of sound from records.

Highly Reliable Protection Circuits

There are protection circuits which serve to detect over-
load and the mid-point voltage in the power amplifier stage.
When the speaker terminals are shorted or something unex-
pected happens that causes the mid-point voltageto under-
go an abnormat change, the circuits use a relay to immedi-
ately cut the power amplifier off from the speakers. They
also function as a muting circuit when the power switch is

set to the ON and OFF positions to suppress the undesira-
ble noise which is generated and to safeguard the speakers
from damage.

Power Level Indicator with Fluorescent Display

Used for the power level indicator are two fluorescent
displays (one for the left channel and the other for the
right) which feature a very fast response speed to indicate
the power level virtually instantaneously. This indicator is
composed of highly dependable ICs and its logarithmic
compression and drive circuits make it possible for a wide
range of power levels from 0.003W right up to the maxi-
mum levels to be indicated for both the left and right chan-
nels independently without switching knobs or levers.

Rich Store of Accessory Functions

0 The phone interference filter switch serves to reduce the
radio-frequency interference from external electronic or
electrical appliances or produces during record play.

0 The subsonic filter switch serves to cut out the low-
frequency noise, which is harmful to your speakers, ge-
nerated by record warp.

o The loudness switch compensates for the deficiencies of
the human ear with respect to low-frequency and high-
frequency sound and it is also useful when listening to
programs at night, for instance, with the sound turned
down.

0 The tone switch is a convenient control for checking the
efficacy of the two tone controls.

9 The function indicators tell you the program source at a
glance.

o The amplifier is provided with two sets (A and B) of
speaker terminals so that you can connect two sets of
speaker systems. This means that you can listen to the
program on one set in another room.

a The amplifier is also equipped with two sets of tape deck
jacks for connecting two tape decks. The tape monitor
switches can be used to dub tapes from TAPE 1 deck to
TAPE 2 deck and for simple tape editing.

0 MODE switch can be used to select between stereo and
mono modes. it is effective in adjusting the balance be-
tween the left and right channels.

o MUTING switch can be used to momentarily reduce the
volume level, or alternatively, you can use it to adjust
the volume subtly in combination with the volume con-
trol knob.

* Measured pursuant to the Federanl Trade Commisions
Trade Regulation rule on Power Output Claims for
Amplifiers.