M-Audio Omni i/o Инструкция по эксплуатации онлайн [8/30] 19296

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.