Front-Panel Layout - PRESONUS FIRESTUDIO MOBILE Owner's Manual

3 CONTROLS & CONNECTIONS
3.2

Front-Panel Layout

3.2 Front-Panel Layout
Microphone Preamplifi er. Your FireStudio Mobile
is equipped with two PreSonus XMAX microphone
preamplifi ers that accept signals from all types of
microphones, as well as instrument-level signals
such as the output of an electric guitar. The PreSonus
preamplifi er design employs a Class A input gain
stage. This arrangement results in ultra-low noise
and wide gain control, allowing the FireStudio
Mobile user to boost desirable signal without
increasing unwanted background noise.
• +14 dBu Headroom. The FireStudio Mobile
microphone preamplifi er has +14 dBu of
headroom. This gives you wide dynamic range and
excellent transient-response characteristics.
• Combo Connectors. Each channel of the FireStudio
Mobile has a Combo mic/line jack that accepts
either ¼" phone or XLR plugs.
Instrument Inputs (Channels 1 and 2). The ¼" TS
connector on Channels 1 and 2 are for use with an
instrument (guitar, bass, etc.). When an instrument is
plugged into the ¼" input, a high impedance input
buff er is switched into the preamp circuit and the
FireStudio Mobile becomes an active instrument
preamplifi er.
NOTE: Don't plug a line-level source into the input jacks
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PreSonus FireStudio Mobile Owner's Manual
of Channels 1 or 2. Active instruments have an internal
preamp and a line-level output and should be plugged
into a line-level input on the rear of the FireStudio
Mobile, not into a front-panel instrument input.
Plugging line-level sources into the instrument inputs
risks damage to the inputs and can result in a very loud
and often distorted audio signal.
LED Meters/Clip Indicator. Channels 1 and 2 feature
3-LED level indicators. The green LED will light up
when an input signal from the XLR (Mic input) or
¼" (Instrument input) reaches -40 dBFS (-30 dBu).
The yellow LED will light up when the channel's
input signal reaches -6 dBFS (+4 dBu). The red clip
indicator LED will illuminate when the channel's
input signal reaches 0 dBFS (+10 dBu). At this level,
the signal will begin to overload the converters and
exhibit signs of clipping, an undesirable type of
distortion. Use the gain controls to keep the signal
below 0 dBFS.
48 Volt Phantom Power. The FireStudio Mobile
has 48V phantom power, available via a single
button switch on the front panel. Phantom power is
available whether your FireStudio Mobile is powered
by the FireWire bus or by its external power supply.
• XLR-connector wiring for phantom power:
• Pin 1 = GND
• Pin 2 = +48V
• Pin 3 = +48V
CONTROLS & CONNECTIONS 3
Front-Panel Layout 3.2
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