Back Panel Layout And Descriptions; Mixer - PRESONUS FIREBOX User Manual

3 CONTROLS AND CONNECTIONS
NOTE: Active instruments are those that have an internal preamp or a line level
output. Active instruments should be plugged into a line input (3 or 4) rather
than into an instrument input. In other words, don't plug an active instrument
into the combo jacks on channels 1 or 2.
3. Input Gain/Trim Control. This knob provides the following gain structure for
each channel:
Microphone Input XLR: 45dB of variable gain (+14dB to +55dB)
Instrument HiZ Input TS ¼" (channels 1 and 2 only): 45dB variable
gain (+8dB to +50dB)
Clip Indicator. The clip indicator will light up if your input signal from the XLR (Mic) or
¼" (line) reaches +18dBu (0dBfs). At this level, your mic preamp/line trim signal may
not exhibit signs of clipping such as distortion. However, this level would cause the A/D
(analog to digital) converters to clip. Therefore it is highly recommended that you do
not allow your converters to clip (the clip indicators to light up) as the sound quality
would not be desirable.
4. Main Level. This knob allows control over the output level for the MAIN CR
OUTPUT 1 and 2 on the back of the FIREBOX. It has a range of -80db to +10dB.
5. Headphone Symbol and ¼" Jack. This is where you connect your headphones.
6. Phones. The Phones knob controls the amount of volume going to the headphone
output on the front of the unit. Notice the volume indicator goes to 11 (loud). Use this
setting with caution.
7. Red-Blue Power/Sync Light. This light is a clock (sync) indicator. It lets you know if
your unit is receiving word clock correctly. Word clock is the manner by which digital
devices sync frame rates. Proper word clock sync prevents digital devices from having
pops, clicks, or distortion in the audio signal (due to mismatched digital audio
transmission).
Blue – solid sync
Red – sync not present.
Flashing Red and Blue – external sync not present
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3 CONTROLS AND CONNECTIONS
MIDI stands for "Musical Instrument Digital Interface". However, the MIDI standard
goes well beyond just instrumentation and sequencing. The MIDI inputs and outputs
allow connection and/or communication with external MIDI equipment. One function of
this port is MIDI programming. This port can also be used for MMC (MIDI Machine
Control) and MTC (MIDI Time Control). Please consult the manual of the software
manufacturer to learn setup and usage of different MIDI applications.
Line Outputs (3, 4, 5, 6). Balanced line level outputs. These connectors will accept
either balanced (TRS – Tip Ring Sleeve) ¼" cables or unbalanced TS (Tip Sleeve) ¼"
cables.
Main CR Output. The level of this output is controlled by the Main volume knob on the
front of the unit.
Line Inputs (3 and 4). These connectors will accept either balanced (TRS – Tip Ring
Sleeve) ¼" cables or unbalanced TS (Tip Sleeve) ¼" cables. The Line Input can also
be used as a standard line level input for devices that do not require pre-amplification
(such as a CD player, drum machine, sampler and etc.).
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3 CONTROLS AND CONNECTIONS
3 . 2 B A C K P A N E L L A Y O U T A N D
D E S C R I P T I O N
12VDC Power Adaptor Input. This is where you plug the provided power supply into
the FIREBOX. Please check the power supply to ensure that it is the correct voltage
and plug type for your country. Note that you can also power your FIREBOX with a six-
pin FireWire port from your computer instead of using the external power supply.
FireWire Ports. There are two firewire ports on the back of the FIREBOX. Both
FireWire ports are standard 6 pin firewire jacks. If your computer has a six-pin FireWire
port you can power your FIREBOX from the FireWire connector. If your computer has
a 4 pin connector, then you will need to get a 4 to 6 pin connector to connect your
FIREBOX to your computer, and use the external power supply. Either port can be
used to connect the FIREBOX to a FireWire port on your computer.
MIDI and S/PDIF IN and OUT.
MIDI and SPDIF I/O can be connected to this DB-9 connector breakout cable
(included). The S/PDIF I/O allows the FIREBOX to receive and transmit audio from/to
other digital audio devices. The S/PDIF standard allows for two channels of audio to
be transmitted at up to rates of 24bit/96Khz. Word clock is the synchronizing signal
that indicates the sampling frequency or rate of sample words over a digital audio
interface. Note: When using SPDIF In, you must select SPDIF in your FIREBOX
Hardware Control Panel.
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4 MIXER

4 . 1 M I X E R
The FIREBOX includes a software MIXER/ROUTER for flexible monitoring and
routing of the audio signal before it hits your software program. This is helpful to avoid
the time it takes to process the audio you are recording – called latency. Therefore,
you can mix the input signal going into the FIREBOX with the playback from your
software for zero latency recording and monitoring.
NOTE: The default settings (pictured above) for the FIREBOX mixer has all faders set
to 0dB and all pans set to center, with the Software Playback set to channels 1/2, the
Mixer Output set to Bypass, and the Playback to Phones set to channels 1/2.
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