6
CONTROLS and OPERATION:
The
Left Gain
and
Right Gain
Controls directly adjust the input amplifiers giving you control over the
dynamic range of your source. You get from 0 to 48dB of gain depending on settings. Set the controls
counterclockwise to minimum gain when connecting the inputs.
The
Monitor Mix
control allows you to directly blend between the internal preamplifier signals and the
playback signals from your computer. When recording new tracks only or just using the
USB Dual
Pre
as a microphone or instrument preamplifier set the Mix control to “Preamp”. When using the
USB
Dual Pre
for USB to audio output monitoring of your computers playback signal, you would set the
Mix control to “Computer”. When set in the middle you get a blend of the direct preamp signal and
signals coming from your computer.
Some recording programs and computer systems provide what is called a “Play-Through” function.
This can be performed through software or hardware. When Play-Through is set to ON, the computer
will output the audio that is being recorded. There is a short delay, or latency with this audio signal.
There is also a potential for the computer’s audio inputs and outputs to be connected together there-
by forming a feedback loop. This can accidentally create very loud and disturbing sounds. Therefore
“Play-Through” is usually set to OFF as the “default” setting in both software and hardware.
If Software/Hardware Play-Through is set to ON and the Monitor Mix is set in the middle, then you will
most likely hear the original preamp signal together with the computer audio signal slightly delayed,
thereby creating an echo effect. This is normal behavior, so while using various Monitor Mix settings it
may be preferable to leave Play-Through set to OFF.
The
Monitor Level
control adjusts overall monitor level after the mix circuitry and before the monitor
output amplifiers. This control affects the signal levels at both the 1/8-inch headphone and 1/4-inch
balanced monitor output jacks.
The
Phantom
power switch, on the rear, a48 Volt phantom power to the XLR input jacks for
powering microphones, if needed. It is slow at turning on and off and is current limited to protect
sensitive microphones and reduce audible pops. It is not lit, even when on, to maximize battery life.
Ideally, when connecting a microphone that requires phantom power, you should first turn down gain,
next connect the microphone, next switch on the phantom power, and finally bring the gain back up to
the desired level. This minimizes pops in your system and stress on the microphone.