Sima Products SELECTORS SSW-4 - Manual (Page 6)

Page 6
Refer to your amplifier or receiver’s user manual or on the rear panel of the
amplifier to determine the minimal speaker impedance that your amplifier can
handle.
If your amplifier can handle 4 ohm loads
4 ohm
speakers 6 ohm
speakers 8 ohm
speakers 16 ohm
speakers
1 selected Protection OFF Protection OFF Protection OFF Protection OFF
2 selected Protection ON Protection ON Protection OFF Protection OFF
3 selected Protection ON Protection ON Protection ON Protection OFF
4 selected Protection ON Protection ON Protection ON Protection OFF
5 selected Protection ON Protection ON Protection ON Protection ON
6 selected Protection ON Protection ON Protection ON Protection ON
If your amplifier can handle 2 ohm loads
4 ohm
speakers 6 ohm
speakers 8 ohm
speakers 16 ohm
speakers
1 selected Protection OFF Protection OFF Protection OFF Protection OFF
2 selected Protection OFF Protection OFF Protection OFF Protection OFF
3 selected Protection ON Protection OFF Protection OFF Protection OFF
4 selected Protection ON Protection ON Protection OFF Protection OFF
5 selected Protection ON Protection ON Protection ON Protection OFF
6 selected Protection ON Protection ON Protection ON Protection OFF
Calculating Impedance
If you want to calculate the impedance of speakers with different impedance here is
how to do it.
Parallel Impedance is equal to (R1 x R2) / (R1 + R2).
Say you had a 6 ohm and an 8 ohm speaker. The parallel impedance if you
selected these two speakers would be:
(6 x 8) / (6+ 8) =48 / 14 = 3.4 ohms.
If the calculated impedance is less than the minimal amplifier allowed impedance,
turn the PROTECTION mode on.