SoundMax SM-CMD2022 - Manual (Page 10)

10
Speaker wiring notes
Follow the above wiring diagram to install the head unit with new or existing speakers.
This unit is designed for use with four (4) speakers with an impedance between 4 Ohms
to 8 Ohms.
An impedance load of less than 4 Ohms could damage the unit.
Never bridge or combine the speaker wire outputs. When not using four speakers, use
electrical tape to tape the ends of the unused speaker outputs to prevent a short circuit.
Never ground the negative speaker terminals to chassis ground.