M-S And X-Y Stereo Recording; Wireless Microphone Power Ditribution - PSC M4 mkII Operation Manual

D.

M-S AND X-Y STEREO RECORDING

The PSC m4mkII Mixer can be used to make stereo recordings in both the mid-
side and X-Y stereo techniques. The M4mkII Mixer is equipped with an input
channel ganging switch designed to allow the ganging of input channels 3 and 4.
This switch is located on the bottom panel of the mixer. When switched to the
"ganged" position, both input channels 3 and 4 are controlled by pot 4. All
microphone powering and attenuation settings remain independent. X-Y stereo
recordings are accomplished by plugging in two identical microphones into
channels 3 and 4. The channel 3 pan pot is set to the extreme left and the
channel 4 pan pot is set to the extreme right. The headphone monitor mode
switch is set to "stereo".
If M-S stereo recordings are desired, the "M" or middle microphone (cardiod
pattern) is plugged into channel 3. The "S" or side microphone (Figure 8 pattern)
is plugged into channel 4. As with the X-Y setup, pan pot 3 is panned to the
extreme left and pan pot 4 to the extreme right. In this case, the headphone
mode switch is set to "MS". In the MS mode, the headphone amplifiers are fed
MS decoded signals. The left headphone amp is fed M-S signals and the right
headphone is fed M+S signals. In this manner, MS signals appear as standard
stereo signals for headphone monitoring purposes. Note that the MS decode
function only affects the headphone feeds, not the main XLR outputs.
More complete descriptions of the M-S and X-Y stereo recording techniques can
be found in the literature of the major microphone manufacturers such as
Neuman, Sennheiser, and Scheops.
E. WIRELESS MICROPHONE POWER DISTRIBUTION
Your new M4mkII Mixer is equipped with two four pin Hirose tm connectors
designed to output DC power to operate you wireless microphone receivers. The
two connectors are located directly below the channel four input XLR connector.
These two connectors are wired as follows:
PIN 1 = GROUND
PIN 4 + POSITIVE BATTERY VOLTAGE.
This is the wiring standard found on most Betacams. Many wireless microphone
makers such as Lectrosonics tm supply cables pre-made for this purpose. If you
make you own cables, please understand that you must match grounding
potentials or risk equipment damage!
M4mkII Mixer has extensive RF filtering built input the power line supplying these
connectors, there remains a possibility that not all wireless frequencies will
operate without interference with either the mixer or other wireless units. Also
note that all current supplied by these connectors is routed through the M4mkII
Mixers Polyfuse (automatic resetting fuse) and thus there are limits to how much
current can be supplied by these connectors. That limit is typically 1 Amp.
Excessive current will cause the Polyfuse to trip and shut off the mixer. To
restore power, simply switch off the mixer, disconnect the offensive load and turn
the mixers power back on.
Please also note that while the new
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