stereo) plug on the 1/4” jacks of the Omni (that are designed for unbal/balanced
operation) will give you this balanced line—tip positive, ring negative, and
sleeve ground. Generally, if the Omni outputs connect to a system or device that
accepts a balanced line at +4dB (nominal level) operating level, you should use
TRS plugs on the outputs.
XLR connectors also carry a balanced signal. If your device or monitoring system
accepts an XLR connector, you may need a cable that has 1/4” TRS to male or
female XLR. The mic input of the Omni Mic/Instr Inputs accepts a male XLR,
with a balanced mic cable being female XLR to male XLR.
5.2 Unbalanced Signals
An unbalanced line on the Omni outputs connects to a 1/4” TS (tip positive,
sleeve ground) plug on a shielded cable with a single conductor, and is
appropriate to use when the device you are connecting to accepts a 1/4” TS plug
or an RCA plug. Typically, the signal on unbalanced lines has an operating line
level of –10dB (nominal level), though this varies somewhat.
You may want to consult the user guide of your sound card or sound system if
you’re not sure what type of signal it can accept. If you need to, find a primer on
recording or sound reinforcement to learn more about this and the other subjects
covered in this manual.
5.3. Phantom Power
Unlike dynamic microphones, large diaphragm condenser microphones need to
receive a DC voltage (generally 48v) from an external source before they can
generate an output signal. If the condenser mic doesn’t come with its own
power supply, then phantom power must be applied from the Omni’s Mic/Instr
pre-amps. Pressing the “Phantom” button and engaging phantom power on the
Omni will send the necessary voltage to both of the XLR Mic Inputs.
Phantom power will not affect a dynamic mic adversely, so its not a problem to
have a dynamic mic at the XLR input while phantom power is switched on.
Some ‘ribbon’ microphones (not very common) may be harmed, however, so
check you mic’s documentation.
5.4 Sends and Returns
These are sometimes elusive terms, as they can be used in a variety of ways. A
“send” is an
output
from a device (such as a mixing console), to another device
(what might be considered ‘outboard’). There is some expectation that the signal
that is sent from the send output is going to “return” to the sending device’s
signal flow. A return is an
input
to a device.
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