Zapco i-Force - Manual (Page 9)

9
i-FORCE Inputs
To provide maximum versatility, i-Force amplifiers provide both RCA
and SymbiLink™ inputs. They also provide Balanced High Level inputs that
can hook directly to your speaker outputs of your factory system.
Below are the wire codes for the Balanced High Level input plugs.
Warning: The black reference ground wire must be hooked up to the
head unit’s chassis ground or performance will be seriously degraded!
Mono and 2 Channel Input Plug
4 Channel Input Plug