Boss Audio Systems BR-900CD owner manual Using Condenser Microphones Phantom Power, Phantom power

Using Condenser Microphones (Phantom Power)

Most condenser microphones need a supply of power known as phantom power in order to operate.

Accordingly, the BR-900CD can supply phantom power at +48 V to condenser microphones connected to any of the XLR-type connectors for MIC 1 and MIC 2.

Phantom power

Condenser microphones generally contain a pair of thin opposing electrodes. When a voltage is applied across these electrodes, any vibration resulting from incoming audio will be output as electrical waves. However, since these waves are very weak, they must be boosted using amplification circuitry within the microphone itself. Phantom power is used to drive this amplification circuitry.

Certain types of condenser microphone use internal batteries as a source of power; accordingly, there will be no need to supply phantom power in such a case.

Notes when using the Phantom power

•Phantom power should always be turned off when audio sources other than condenser microphones are being connected to the BR-900CD’s. In fact, dynamic microphones, audio players, and the like can be damaged by this power supply. Always refer to the user’s manual for the microphone to be used in order to confirm its phantom-power specifications.

•A supply of phantom power is not needed for certain types of condenser microphone (i.e., microphones featuring internal batteries, electric condenser microphones, etc.). Ensure that phantom power is set to “OFF” whenever one of these microphones is connected.

•The BR-900CD’s MASTER fader, INPUT SENS GUITAR/BASS/MIC2 and MIC knobs, and INPUT LEVEL knobs must be moved all the way down when phantom power is being turned on or off. If this precaution is not observed, there is a possibility that amplifiers, speakers, and the like may be damaged by loud noises generated upon switching.

1.Before proceeding, turn INPUT SENS GUITAR/BASS/ MIC2 and MIC knobs fully counter-clockwise in order to reduce the input volumes, and then move the MASTER fader and INPUT LEVEL knobs all the way down.

If any of these volumes is not reduced, a loud click may be output when the phantom power is turned on or off.

2.Press [UTILITY].

The Utility screen will appear.

3.Press CURSOR [ ] [ ] to move the cursor to “SYS,” and press [ENTER].

4.Press CURSOR [ ] [ ] to select “Phantom SW,” and

turn the TIME/VALUE dial to turn the setting “ON.”

fig.05-504d

ON: Phantom power will be supplied.

Note that when turned on, phantom power will be supplied to all XLR connectors for MIC 1 and 2.

OFF: Phantom power will not be supplied.

5.Slowly raise the INPUT SENS knobs, the MASTER fader and INPUT LEVEL knobs, and confirm that an audio signal is being received from the condenser microphone(s).

6.To turn off the phantom power, repeat Steps 1 through 3, and then set “Phantom SW” to “OFF” in Step 4.

•Phantom power cannot be turned on or off individually for MIC 1 and 2.

•Phantom power is not supplied to the 1/4” phone jack for MIC 1 or to the GUITAR/BASS jack.

•The phantom power setting reverts to “OFF” whenever the BR-900CD is turned on. Remember, therefore, to turn on this power supply whenever it is needed.

•No supply of phantom power will be needed from the BR-900CD when using an external microphone pre-amp or a dedicated, external phantom power supply. Ensure that phantom power is set to “OFF” in all such cases.

Section 8

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