TOA Electronics 1000 Series - Manual (Page 6)

Input/Output Connections
Input terminal from mixer, etc.
Input terminal from mixer, etc.
E-1231
E-1231
Power Amplifier
Speaker System
Installation Precautions
Ground Loops
In any audio system, there are numerous ways by which ground loops can be created.
For example, they may occur when the E-1231 is mounted in a rack cabinet, or
through AC ground when the E-1231 connected with preamps, mixers, etc. These
ground loops may cause hum and noise if care is not taken during connection. An
increase in noise from ground loops may be minimized by breaking the ground loop.
Generally, the chassis ground of the signal line should be broken as shown below.
When hum is generated from a ground loop, detach a short piece from the ground
screw terminal.
— 6 —