Sony ST-RDE945 Operating Instructions Manual page 17

To avoid short-circuiting the speakers
Short-circuiting of the speakers may damage the receiver.
To prevent this, make sure to take the following
precautions when connecting the speakers.
Make sure the stripped ends of each speaker cord
do not touch another speaker terminal or the
stripped end of another speaker cord.
Examples of poor conditions of the speaker cord
Stripped speaker cord is touching another speaker terminal.
Stripped cords are touching each other due to excessive
removal of insulation.
After connecting all the components, speakers,
and AC power cord, output a test tone to check
that all the speakers are connected correctly. For
details on outputting a test tone, see page 22.
If no sound is heard from a speaker while outputting a
test tone or a test tone is output from a speaker other than
the one whose name is currently displayed on the
receiver, the speaker may be short-circuited. If this
happens, check the speaker connection again.
Speaker impedance
To enjoy multi channel surround, connect front, center,
and rear speakers with a nominal impedance of 8 ohms or
higher, and set the speaker IMPEDANCE SELECTOR to
"8 ." Check the instruction manual supplied with your
speakers if you're not sure of their impedance. (This
information is usually printed on a label on the back of
the speaker.)
You may connect a pair of speakers with a nominal
impedance between 4 and 8 ohms to the FRONT
SPEAKERS terminals, if you set the IMPEDANCE
SELECTOR to "4 " Speakers connected to the REAR and
CENTER SPEAKERS terminals must have a nominal
impedance of 8 ohms or higher (regardless of the setting
of the IMPEDANCE SELECTOR).
Note
Be sure to connect front speakers with a nominal impedance of
8 ohms or higher if you want to select both sets (A+B) of front
speakers (see page 27). In this case, set the IMPEDANCE
SELECTOR to "4 ".
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