Harman Kardon TC300 Owner's Manual page 15

Option 1: Connect two 10-gauge or larger
Option 2: Connect a single 4-gauge or
wires to the positive terminal on the larger lead to the positive terminal on the
battery. Within 18" of the battery battery. Within 18" of the battery
terminal, insert a 45-amp fuse, fuseable terminal, insert a 90-amp fuse, fuseable
link, or circuit breaker in each lead.
link or circuit breaker in the lead. Run
Connect each lead to one of the two the single lead to the area where you have
battery (+) terminals on the TC600.
mounted your TC600, then use a splitter
to split to two 10-gauge leads that then
connect to the two battery
+
terminals on
the TC600.
12V Ground ( E L ) connection
Connect two 10-gauge or larger wires to the
two ground
(-)
connectors on the TC600,
then run both leads to the same point on the
metal chassis of the car. Make sure you
scrape down to bare metal, and make sure
that the metal is directly part of the main
vehicle chassis. Keep the ground leads as
short as possible.