Array (under the VU meter) for a visual reference to the Pro Channel’s internal signal
levels.
Hint:
the “sweet spot” for the Pro Channel is when all 4 of the yellow “warm”
LEDs in the Tube Character Array are lit.
Gain Switch
Use the Gain switch to set the range of the Gain control – depressing the switch
adds
20dB to the gain range described above. With the switch
in
, the gain range is +9 to
+50dB using the unbalanced input (or +21 to +62dB Balanced).
Note:
With most
microphone applications you’ll find it necessary to use the Pro Channel with the +20dB
gain switch in. Use the setting that best fits your application.
Phantom Power Switch
The Pro Channel can power any microphone n48 volts DC phantom power.
Consult your microphone’s documentation to see if phantom power is required. Turning
the phantom power switch
On
supplies power to pins 2 and 3 of the balanced XLR
input jack.
Note:
It is best to have phantom power turned off when connecting microphones to the
Pro Channel.
Note:
Be sure to turn down or mute the output of the Pro Channel when engaging or
disengaging phantom power. Additionally, when disengaging, allow 30 - 45 seconds
for the power to completely dissipate. Most microphones will make a sound like air
leaking from a tire when phantom power is disconnected, but some can make some very
nasty low rumbles and whines as well.
Another Note:
MOST dynamic microphones should not be affected or damaged if they
are plugged into the Pro Channel when phantom power is turned on (we haven’t run
across any). However,
if the mic doesn’t need it, don’t use it
. Some things are best left
untested!
Phase Switch
The Phase switch is provided to reverse the phase of the signal leaving the Pro
Channel’s preamp section. The Phase switch reverses the polarity of the Preamp Output
jack and everything after it in the signal chain. In the Normal (out) position, the signal
is in-phase. In the Reverse (in) position, the polarity of Pins 2 and 3 of the Output XLR
jack (and the Tip of the ¼” jacks) are reversed and the signal is changed to 180 degrees
out of phase with the input signal. In multiple microphone applications, mic placement
can affect the phase of a signal. If two microphones pick up the same signal from
different locations, the result can be a hollow or frequency “shifted” sound. In some
cases it may sound as if an instrument disappears if it happens to be 180 degrees out of
phase. Depressing the Phase switch can remedy this problem. Likewise, if a
microphone cable is wired incorrectly, the signal will be also out of phase.
Note:
In
single
microphone applications, switching the phase will produce no audible
change in the output signal.
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