User`s guide

User's Guide QuadMic © RME
5
6. Operation and Usage
6.1 Controls
The front of the QuadMic has the gain knobs, switches for low cut, phantom power and phase,
and several status LEDs:
+48V (LED) lights up when phantom power is active. Phantom power should only be activated
when using condensor microphones which require such a power supply.
The CLIP LED lights up 3 dB before the input is
overloaded. Referenced to the output level it lights
up at around +18 dBu.
SIG (Signal) indicates the presence of an input
signal. The threshold of –27 dBFS is rather high
compared to other equipment. With this, SIG also
indicates a useful output level, which is maintained
by a correctly done GAIN adjustment.
The GAIN knob allows for a step-less and precise
adjustment of the amplification between +6 dB and
+60 dB.
+48V (switch) activates phantom power. Phantom power should only be activated when using
condensor microphones which require such a power supply, and only on the specific channel.
Another important rule: plug-in the microphone first, then switch on the phantom power. The
QuadMic will apply the voltage smoothly (soft start). In case the microphone is plugged in while
phantom power is already switched on, a current peak (spike) is generated that can destroy the
sensitive microphone input stages.
LO CUT activates a hi-pass at 80 Hz, 18 dB per octave. This filter can remove rumble and other
low frequency noise.
PHASE changes the polarity. Phase cancellations and sound changes can be caused by using
multiple microphones at different places, or wrongly soldered cables. In such cases PHASE can
eliminate the error by adding an additional phase inversion.
The back of the QuadMic has the 4 analog inputs and outputs and the power supply connector.
MICROPHONE / LINE INPUTS: 4 Neutrik XLR / TRS combo jacks. Thanks to the servo bal-
anced designs and a high maximum input level, the inputs can be used balanced or unbal-
anced, with XLR or TRS jack, with microphone as well as line levels.
LINE LEVEL OUTPUTS: 4 TRS (stereo) jacks. The electronic output stage is built in a servo
balanced design which handles monaural (unbalanced) and stereo jacks (balanced) correctly.
Power: Connect power supply, lead-battery or battery. See chapter 5, Power Supply.