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220 / March 2000
V I R T U A L D I P S W I T C H
In the lower right corner of the VDip screen (figure 8) there are eight
mutually exclusive radio buttons for selecting the desired input attenua-
tion. The attenuation choices are 0db to -14dB in 2 dB steps. Simply click
on the appropriate radio button to select the attenuation value and then
“WRITE” the selected change to the module. You can use the “Write Slot”
toolbar icon or the “Slot” menu item to write the current attenuation setting
along with any other module settings. The attenuation setting is immedi-
ately written to the corresponding channel.
Why use digital attenuation?
Many of today’s digital audio sources (especially modern rock, rap,
etc.) are produced to take full advantage of the available maximum digital
output level (0dBFS). Playback of these tracks from a CD player’s digital
output result in average digital domain levels -6 to -3dBFS or higher! That
translates to average analog levels of +18 to +21 dBu; very close to the
console’s clipping point of +24dBu. Connecting the digital output from a
CD player to a console input with gain on the fader can put the operator in
a position of potentially clipping the CD playback. In this case, adding -
12dB of attenuation will re-calibrate the input module so that digital
clipping of CD source material will be impossible even if the operator
pushes the fader all the way to the top.
Figure 8
220 / May 2001