PRESONUS Firestudio Project User Manual page 33

CONTROLS AND CONNECTIONS

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 buffer is switched into the preamp circuit and the FireStudio Project becomes an active
instrument preamplifier.
NOTE: Active instruments are those that have an
instruments should be plugged into a line input rather than into an instrument input. Plugging a line-
level source into the instrument inputs on the front of the FireStudio not only risks damage to these
inputs but also results in a very loud and often distorted audio signal.
Therefore, don't plug a line-level source into the combo jacks of channels 1 or 2.
-10 0 60 +30 -10 0 60 +30
1 2

Input Gain/Trim Control. These knobs provide the following gain structure:
XLR Microphone Inputs.
o
TS ¼" Instrument/Hi-Z Inputs.
o
TRS ¼" Line Inputs.
o
1 2
48V 0dB
-6dB
-40dB
1/ 2

LED Meters/Clip Indicator. Each channel features three LED level indicators. The green LED will light
up when your input signal from the XLR (mic input) or ¼" (line 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.
FIRESTUDIO ™
1
Mic Instr ument
-20 0 60 +20 -20 0 60 +20 -20 0
3 4
54 dB of variable gain (-4 dB to +50 dB)
54 dB of variable gain (-4 dB to +50 dB)
32 dB of variable gain (-16 dB to +16 dB trim adjustment)
3 4 5
48V 0dB
-6dB
-40dB
3/ 4
30 | PreSonus 2009
2
internal preamp or a line-level output
60 +20 -20 0 60 +20 -20 0
5 6 7
6 7
48V 0dB
-6dB
-40dB
5/ 6
. Active
60 +20 -20 0 60 +20
8
8
48V
7/ 8