Plugs And Jacks; Balanced Cabling & Connections; Unbalalanced Cabling & Connections - M-Audio Omni I/O Manual

Sends and returns are generally spoken of in terms of the gear that is receiving
the signal. The "effects send," therefore, is an output from the mixer to the effect.
The effect's input receives the signal from the "effects send," and the output of
the effects device returns the signal to the mixer's input, the "effects return."
The terms "sends and returns" can apply to other devices, such as a recording
device. The outputs of mixing board are "sent" to a tape deck, for instance, and
the outputs of the tape deck "return" to the mixing desk's monitor channels for
mixing (often called "tape returns," though "tape sends" are more often known
as the buss outs).
In this same sense, the analog outputs of the Delta card, i.e., Delta H/W Outs 1-
4, "return" to the Omni mixer. They could properly be called the "Delta returns
to the Omni mixer."

5.5 Plugs and Jacks

In general, a jack is a female connector, and a plug is a male connector. The jack
is mounted within the hardware device, and the plug exists on the cable ends.
XLR jacks and plugs, however, may be male or female. Usually, the output is
male, and the input is female.
5.6 Balanced Cabling & Connections
The acronym "TRS" stands for Tip-Ring-Sleeve. A 1/4" TRS plug can carry a
balanced mono audio signal over a two-conductor cable with a shield, which
applies to certain TRS jacks on the Omni. This may be considered a standard
1/4" "stereo cable," though it carries a mono, balanced signal.
If you are using one of the Omni jacks for balanced operation, you will need a
cable with a 1/4" Tip-Ring-Sleeve plug on one end (for the Omni jack), and a
plug on the other end that is appropriate for the device that you are connecting
to. This may be a 1/4" TRS plug, an XLR plug, an 1/8" TRS plug, etc.
5.7 Unbalalanced Cabling & Connections
The acronym "TS" stands for Tip-Sleeve. A 1/4" TS plug is found on what is
commonly referred to as a "guitar cable." This is a single conductor cable with a
shield, and is generally associated with unbalanced operation.
If you are using one of the Omni jacks for unbalanced operation, you will need a
cable with a 1/4" Tip-Sleeve plug on one end (for the Omni jack), and a plug on
the other end that is appropriate for the device that you are connecting to. This
may be a 1/4" TS plug, an RCA plug, an 1/8" TS plug, etc.
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