Sound Devices 664, User Manual

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37
INPUTS
To configure channel linking:
1. Press the MENU button.
2. Turn and press the Headphone encoder to select INPUTS and then which
input pair to link. Options include: Ch 1-2 Linking, Ch 3-4 Linking, or Ch 5-6
Linking.
3. Turn and press the Headphone encoder to set linking, indicated by pairs.
Options include: Unlinked, Linked (pair), or Linked (pair) MS.
For instance, selecting 1-2 configures channel linking for input pair 1 and 2.
Selecting 3-4 MS, configures Mid-Side linking for input pair 3 and 4.
Mid-Side Linking
When input pairs are linked MS, the odd channel is used for the Mid signal and
the even channel is used for the Side signal. To produce a stereo signal from an
MS configuration, the signal from both microphones must be processed.
Mid Signal
Side Signal
Mid-side matrixing is a method for processing audio signal from a cardioid
microphone and a bidirectional microphone into a stereo
signal. The cardioid microphone is the Mid signal and
connects to the odd input, and the bidirectional
microphone is the Side signal and connects to even
input. The cardioid microphone is pointed at the sound
source, and the bidirectional microphone is oriented
sideways—positioned with its capsule as near as
possible to the cardioid microphone’s capsule. The
diagram shows the relative polar patterns of
microphones in an MS configuration.
Configuring Phantom Voltage
Phantom powering is a fixed DC voltage of either 12 or 48 volts. This voltage is
resistively applied to pin 2 and pin 3 of an input’s XLR-3F connector, relative to
pin 1. In this configuration, there is no voltage difference between signal pins 2
and 3. On the 664, the factory default sets phantom power to 48 volts, but that
may be changed.
To configure phantom voltage:
1. Press the MENU button.
2. Turn and press the Headphone encoder to select INPUTS > Phantom Volt -
age.
3. Turn the Headphone encoder to change the setting. Options include: 48V or
12V.
This setting globally adjusts the voltage level of phantom power on all
inputs with phantom power enabled.