Pioneer SA-708 - Block Diagram; Circuit Descriptions; Phono Circuit; Tone Controls Circuit

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SPEAKER SYSTEM CONNECTIONS (Fig. 1)
The amplifier is provided with two sets of SPEAK-
ERS output terminals. Use the A set when con-
necting only one set of speakers. Viewed from the
front, the R (right channel) SPEAKERS terminals
are on the right and the L (left channel) SPEAK-
ERS terminals are on the left. Connect the left
channel speaker to the L terminals and the right
channel speaker to the R terminals. The red L and
R SPEAKERS terminals have a plus polarity and
the black terminals have a minus polarity and the
speaker systems have also the same dual polarities.
When connecting, always connect minus to minus
and plus to plus.
Cautions when connecting the speakers
1. The speaker output terminals have polarities:
minus (black) and plus (red). The input jacks on
the speakers also have plus and minus polarities.
When connecting, make sure that these polarities
are aligned: plus to plus and minus to minus. If
the left and right speaker polarities are mis-
aligned, the reproduced sound will not display a
natural stereo effect.
2. Use speakers with a nominal impedance ranging
from 4 ohms to 16 ohms.
3. Never use the speakers with the speaker output
terminals shorted (minus and plus jacks con-
nected) since this may damage the power transis-
tors in the amplifier.
Processing and connecting the speaker cords
(Fig. 2)
1. Cut off the covering of the speaker cords as
shown in Fig. 2- @.
2. If the strands at the tip of the cord are pointing
in all directions, twist them with your thumb
and forefinger. Otherwise some of the strands
may come into contact with other terminals and
cords, and cause a short.
3. Push down on the buttons under the terminals
with the tip of your finger, and slip the tip of
the cord into the hole in the center of the
terminal. Make sure that the lead wire in the
cord does not protrude.
4. Remove your fingertip from the button. The
- terminal will snap back into position and so
check that the cord is securely connected. You
may not hear any sound if the cords are not
connected properly.
Right channel
speaker system
SPEAKERS
terminals
Connect your second pair
of speaker system.
Left channel
speaker system
Fig. 1
Speaker lead wire preparation
and connection
Fig. 2