Controls and connections, 12 firestudio – Presonus Audio electronic Recording Interface w/ Eight Microphone Preamplifiers Version 1.0 User Manual
Page 24
CONTROLS AND CONNECTIONS
22 | PreSonus 2007
• 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 instrument input, the
microphone preamp is bypassed, and the FireStudio Project becomes an active instrument preamplifier.
NOTE: Active instruments are those that have an
internal preamp
or a
line level output
. Active
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 Project not only risks damage to
these inputs but also results in a very loud and often distorted audio signal.
(In other words, don’t plug a line level source into the combo jacks of channel 1 or 2.)
• Input Gain/Trim Control. These knobs provide the following gain structure:
o
XLR Microphone Inputs.
54 dB of variable gain (-4 dB to +50 dB)
o
TS ¼” Instrument/Hi-Z Inputs.
54 dB of variable gain (-4 dB to +50 dB)
o
TRS ¼” Line Inputs.
32 dB of variable gain (-16 dB to +16 dB trim adjustment)
• 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) or ¼” (line) reaches -40 dBFS. 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. At this level, your mic preamp/line trim
signal will exhibit signs of clipping such as distortion. It is highly recommended you do not allow your
converters to clip (the red clip indicators to light up) as the sound quality will not be desirable.
Mic Inst r ument
1
2
FIRESTUDIO
™
60+20
-20 0
60+20
-20 0
60+20
-20 0
60+20
-20 0
60+20
-20 0
60+30
-10 0
60+30
-10 0
1
2
3
4
60+20
-20 0
5
6
7
8
0dB
-6dB
-40dB
0dB
-6dB
-40dB
0dB
-6dB
-40dB
3/ 4
48V
5/ 6
48V
7/ 8
48V
1/ 2
48V
1
2
3
4
5
6
7
8