34
• When connecting an unbalanced output
to a balanced input, be sure that the signal
high (hot) connections are wired to each
other. The unbalanced ground (earth) connec-
tion should be wired to the low and the ground
connections of the balanced input. If there are
ground-loop problems, try connecting the un-
balanced ground connection only to the input
low connection, and leaving the input ground
connection disconnected.
• In some cases, you will have to make up
special adapters to interconnect your equip-
ment. For example, you may need a balanced
XLR female connected to an unbalanced 1⁄4"
TS phone plug. The balanced-to-unbalanced
connection has been anticipated in the wiring
of Mackie jacks. A 1⁄4" TS plug inserted into a
1⁄4" TRS balanced input, for example, auto-
matically unbalances the input and makes all
the right connections. Conversely, a 1⁄4" TRS
plug inserted into a 1⁄4" unbalanced input
automatically ties the ring (low or cold) to
ground (earth).
BINDING POSTS
Binding posts provide a number of different
methods for connecting speaker wire to the
outputs of the amplifier. For fixed installations,
you can use bare wire (Figure D), or wire termi-
nated with spade lugs (Figure E).
For portable applications, the binding posts
accept single or double banana plugs (Figure
F). They provide a method of quickly connect-
ing and dis- connecting speaker cables to and
from the amplifier. Double banana plugs have a
tab on one side to indicate the ground (GND)
side of the connector. This side connects to the
black (–) binding post terminals on the amplifier.
G
N
D
Figure D: Binding Posts
with Bare Wire
Figure F: Binding Posts with Double Banana Plug
1/4"
Figure E: Binding Posts
with Spade Lug
