Proel DB2A - Manual (Page 2)

RACK MOUNTING
Simply removing the two molded sides and attaching two units with the supplied brackets you can mount two by
two DI boxes into a standard 19” rack.
SPECIFICATION
EXAMPLES
CONTROLS AND AUDIO CONNECTION
1. INPUT - (unbalanced JACK or RCA)
Connect the source instrument to this 1/4” jack or rca pin socket to receive the signal. The input impedance depends
by PAD setting: 200 Kohm with no pad, 47 Kohm with pad insertion.
2. LINK - (unbalanced JACK)
Connect this 1/4” jack to the input of the backline instrument or monitor amplifi er.
3. PAD - (switch)
The pad switches reduce the input signal to the circuit to ensure a clean and distortion-free signal.
Three steps are possible: 0 dB (no pad), -20 dB, -30 dB. Always use as little as attenuation as possible to get the
best possible signal with reference to the noise fl oor.
4. BAL OUTPUT - (male XLR)
This male XLR output connector is the balanced microphone level output of the DI and it is wired with pin-1
ground, pin-2 hot and pin-3 cold. To power the DI box it must be connected to the phantom powered MIC input
of the mixing console. Connecting the DI box to a mixer LINE input the DI box must be powered with battery or
AC/DC adaptor.
5. GND LIFT - (switch)
Use the GND LIFT switch to either connect the ground pin of input and output or keep them partially separated.
Depending on the grounding of the connected devices linking or disconnecting will reduce hum and buzz noises
and prevent ground loops.
NOTE: The proprietary GND LIFT circuit especcially developed for DB2-A doesn’t allow to connect this unit
directly to speaker terminals: please don’t use this unit connected to high level amplifi er outputs.
6. POWER - (switch)
The power switch is used for both battery and external adaptor power. To avoid battery drain when the unit is not in
use, ensure that this switch is set to the OFF position when storing the DB2-A. The power switch has not infl uence
when the DB2-A is powered by the phantom power of a MIC channel.
NOTE: To prevent damaging of your speaker and avoid switching noise, fi rst connect the DI box and then
hook up the respective channel or mute the mix channel before activating or connecting the DB2-A.
7. ON - (green led)
The ON (green) led shows when the DB2-A is powered. If the led doesn’t light, be sure that the phantom power of
the channel where the DB2-A is connected is activated.
NOTE: DB2-A needs the phantom power from at least one channel, in any case we suggest to send the
phantom power from both channels if connected: this ensure a second power safety option.
8. 9V BATTERY HOLDER
For best reliability and long life, we recommend you use only high quality alkaline battery.
9. 9VDC INPUT/LINK
Alternatively to phantom or battery power you can use also an external 9 V DC adaptor. A LINK socket is provided
if you have to power more than one unit installed into a rack.
System Type 2 channel active DI System Performance
Input Section Insertion loss < 1 dB
Input Impedance 200K Ohm (pad at 0 dB) CMR > 40 dB
47k Ohm (pad at -20 dB) Phase distortion +4° at 20 Hz, -13° at 20k Hz
44k Ohm (pad at -40 dB) Distortion THD 50÷20k Hz 0dBu < 0.007 %
Max Input Level +5 dBu (pad at 0 dB) Noise < -105 dBu unweighted
+25 dBu (pad at -20 dB) Frequency Response 10 Hz to 70 kHz, +0dB/-1 dB
+35 dBu (pad at -30 dB)
Controls On/off, Pad -20, Pad -30, Gnd Lift.
Connectors Two Parallel 1/4" jack connectors and one Indicators On
parallel RCA connector (unbalanced)
Jack: Tip Hot / Sleeve Ground
General
XLR female: Pin 2 Hot / Pin1 & 3 Ground Phantom Power +24 volts DC to +48 volts DC
Output Section External AC/DC adaptor +9 volts DC
Output Active discrete devices (transformer less) Standalone/Standby 9 volt PP3 type, battery preferably alkaline.
Max. Output Level into 600 Ohms or greater Current consumption less than 8 mA
+5 dBu (for 0.1% THD at 50 Hz)
+5 dBu (for 0.1% THD at 1k Hz)
Dimensions (W x H x D) 215 x 50 x 125 mm
Connector XLR male: Pin 2 Hot / Pin 3 Cold / Pin1 Ground Weight (excluding batteries) 1 Kg
or
to mix desk1
to mix desk2
LEFT CH
(unbal) RIGHT CH
(unbal)
jack-jack link
hi-z pickup (jack unbal)
long cables (XLR balanced)
linking with a jack-jack cable you
can split the signal to each output
linking with a jack-jack cable
you obtain two mono channels
SPLIT