dbx 786 Manuale d'uso - Pagina 9

Sfoglia online o scarica il pdf Manuale d'uso per Amplificatore dbx 786. dbx 786 16. Precision mic preamp

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A: 16dB Cut @ 5kHz; 6dB/Octave Slope

B: 16dB Cut @ 5kHz; 12dB/Octave Slope

C: -∞ Cut @ 5kHz; 6dB/Octave Slope

D: -∞ Cut @ 5kHz; 12dB/Octave Slope

Figure 4: Audio Precision plots of the 786's EQ section.

Peak LED

The Peak LED is located to the left of the VU Meter. It is set to light when the signal level is within

3dB of hard clipping. The LED monitors three different points in the signal path: output of the Gain

control stage, the output of the Fine control stage, and the output of the EQ stage.

VU Meter

The VU Meter is a custom dbx meter and monitors the output signal of the 786. It is calibrated at

0VU=+4dBu.

+48V Phantom Power Switch and LED

This switch activates phantom power for condenser microphones on pins 2 and 3 of the XLR mic input.

Make sure to connect your microphone before activating the phantom power to prevent high voltage

arching, which may damage your microphone.

Super Low Z Input Switch and LED

Typically microphones have an output impedance of 150Ω. The 786 is set to operate in this range with-

out any adjustments necessary. In some instances, a microphone may operate at a much lower imped-

ance, like 20Ω. (ie: some ribbon microphones) The Super Low Z switch optimizes the input circuit of

the 786 for proper damping of these low impedance microphones, and to ensure that the input trans-

former is always fed by the same impedance for consistent performance.

20dB Pad Switch and LED

This switch inserts a 20dB attenuator circuit into the signal path from the microphone input. The pad is

inserted before the signal is routed through the mic pre gain stage. Use the 20dB pad to attenuate sig-

nals from hot sources such as high output microphones, or when the source is a line level device.

Phase Reverse Switch and LED

This switch inverts the phase of the input source 180°. Note that it usually takes years of engineering

experience to properly hear phase relationships. If your console has a phase relationship meter, you may

choose to do "A-B" comparisons with the phase reverse switch in both positions for best results. Out of

phase signals are more obvious in the lower frequency range, due to the size of the waveforms. Out of

phase signals may sound "empty", "hollow", or "weak" in the low frequencies. Use the phase reverse

switch to determine if the source device is out of phase with the rest of the program material.

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controls

786

A: 16dB Boost @ 12kHz; 12dB/Octave Slope

B: 16dB Boost @ 12kHz; 6dB/Octave Slope

C: 16dB Cut @ 12kHz; 6dB/Octave Slope

D: 16dB Cut @ 5kHz; 12dB/Octave Slope

Operating