1. Electrical. A device allowing modern three-prong cords to be inserted in older, two-wire receptacles. For proper operation, the ground
lug or wire
MUST be attached to the faceplate screw. These should NOT
be used to solve audio hum or buzz issues, and their use most likely violates all current
2a. Audio. A male XLR3 to female XLR3 with no connection between the #1 contacts. More correctly should be termed a "Pin 1 Lift."
Whirlwind / Specialty Interface Devices
See this thread
2b. Audio. A rocker or toggle switch
, most often found on a direct box
, that accomplishes the above.