Normals is a common term that refers to the 'normal' or regular path of a signal in a patching system. When a signal is rerouted, it is considered to be breaking the 'normals' and the main function of normalled jacks (sockets) is to eliminate the need for either looping plugs or a permanently placed patchcord in the circuit.
Full Normals (or fully normalled):
- Top and bottom jacks (in a patchbay) have T, R, S, TN, and RN contacts. In a wired patchbay, the two TN terminals are tied together as are the RN terminals.
- Allow for a continuous signal flow without the use of a patchcord or looping plug.
- Allow the user to reroute source (top row of jacks), destination (bottom row of jacks), or both signals.
- Typically found connected to a mixing console.
- On unwired patchbays, user must tie (connect) the top and bottom normal circuits together.
Half Normals (or half normalled):
- Top jacks have T, R, S, while bottom jacks have T, R, S, plus TN and RN. In a wired patchbay, T and R on top are tied to TN and RN on the bottom jacks.
- Acts as a monitor to allow the user to listen in on a signal without interrupting it.
- Acts as a Y junction to allow the user to send a signal to two different destinations.
Non Normals (or non-normalled):
- Top and bottom jacks have T, R, S only.
- Only useful as a cost-saving measure.
- Typically used in applications where no standard signal path will take place.
- Require a patchcord or looping plug to continue signal flow.
Internally shunted
- Means tip, ring and sleeve contacts etc are internally connected to the tip, ring and sleeve contacts, etc, of the jack below.
Abbreviations: FN - Full normals; HN - half normals; NN - no or non-normals; T - terminal that mates with tip of jack plug; R - terminal that mates with ring of jack plug; S - terminal that mates with sleeve (ground) of jack plug; TN - tip normal terminal; RN - ring normal terminal.