Mackie MAINSTREAM - 48 V Phantom Power Switch; 1;8 Headset Jack (Channel 1); Direct Monitor Switch

MAINSTREAM COMPLETE LIVE STREAMING & VIDEO CAPTURE INTERFACE WITH PROGRAMMABLE CONTROL KEYS
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48V Phantom Power Switch
Most modern professional condenser mics require 48V phantom power which lets the mixer send low-current DC voltage
to the mic’s electronics through the same wires that carry audio. (Semi-pro condenser mics ofen have batteries to accomplish
the same thing.) “Phantom” owes its name to an ability to be “unseen” by dynamic mics (Shure SM57/SM58, for instance),
which don’t need external power and aren’t aected by it anyway.
Press this switch in if your microphone requires phantom power. (Always check the position of this switch before connecting
microphones.).
Never plug single-ended (unbalanced) micro phones, or ribbon mics into the mic input jacks if phantom power
is on. Do not plug instrument outputs into the mic XLR input jacks with phantom power on unless you know
for certain it is safe to do so. Be sure that the mic level control is turned down (and/or the mic mute button
is engaged) when connecting a microphone to the mic input when phantom power is turned on to prevent
pops from getting through to the speakers.
/8" Headset Jack [Channel ]
This is a female /8" TRRS connector that accepts a line-level signal from a gaming headset.
It is mono mic-level input and a stereo output of the headphone mix.
The input level is controlled via the mic level control knob, located on the front of MainStream. [It’s the big one located
on the lef-hand side of MainStream; for reference, the silkscreen printed underneath the knob displays a microphone
and headset.].
The output level is controlled via the headphones level control knob, located on the front of MainStream. [It’s the big one located
on the right-hand side of MainStream; for reference, the silkscreen printed underneath the knob displays a set of headphones.].
Warning: The headset amp is loud and could cause permanent hearing damage. Even intermediate levels
may be painfully loud with some headsets. BE CAREFUL! Always turn the volume knob all the way down
before connecting headsets. Then turn it up slowly as you listen carefully.
While channel ’s XLR mic supports 48V phantom power, this /8" mic / headset does not.
However, this jack does add an extra +5V of “plug-in power”.
While channel  ties this /8" TRRS jack and the combo jack below it, they will not work simultaneously.
The XLR input takes precedence.
Direct Monitor Switch
Engage this switch to monitor the input signals. The input signals will then be routed to the headphones and monitors.
The input monitoring occurs in the analog domain, resulting in zero-latency.
If you want to hear your processed voice coming back through the PC return from the computer, then make sure that this switch
is disengaged. Note that there may be some audible latency.