The Unika DI-BOX2 is a 2 channels active direct box, it is very easy to use, simply plug it in, turn on the power and it goes to work. However, there are a number of features built in that should be understood in order to get the most out of the DI-BOX2.
Instrument direct input & Parallel link connection
As with all audio gear, always ensure audio system levels are turned down or equipment turned off before making connections. This will avoid plugin or turn-on transients from damaging more sensitive components such as tweeters.
There are two channels on the DI-BOX2. These are identical and feature XLR-¼”TRS combo jack INPUT, a ¼” thru-put LINK and a balanced XLR OUPUT.
Connect your source instrument to the input and the balanced XLR output to the PA system or recorder. The LINK connector output provides the means for connecting the signal to a stage amp or personal monitor system. Simply connect the LINK to your amp or monitor. Unbalanced cables are much more susceptible to noise than their balanced counterparts. Keeping unbalanced cables under 8 meters (25’) in length is good practice while balanced cables can easily extend to 100 meters (300’). The balanced output of the DI-BOX2 is mic level, meaning that it should be connected to the mic input of a mixing console or mic preamp. Once connected, make sure phantom power is activated.
INPUT PAD ATTENUATION
The most common use of the direct input is with guitar pick-ups or keyboards. The optimal setting for this is most likely with the pad switch set to 0dB, although with some high-output pick-ups the performance of the direct input may be improved if the pad switch is set to -20dB to prevent possible clipping of the input signal. The instrument is connected to the XLR-1/4″ Combo jack socket, and a parallel link feed taken from the other jack socket to the instrument’s own amplifier. The direct input can also be fed either from a line-level output from the head (pad set to -20dB) or from the amplifier power output (speaker output, pad set to -40dB). ELIMINATING HUM AND BUZZ AND THE GROUND LOOP The DI-BOX2 is equipped with output isolation transformers to eliminate hum and buzz caused by stray DC voltage and ground loops. Computers, optical projectors and other consumer equipment can be particularly noisy, anyone that has incorporated audio with a projector knows that noise can be a serious problem, so transformers can be incredibly useful when combating system noise. A ground lift switch on the outputs takes this one step further by lifting pin-1 on the XLRs. Computers are often the source for noise problems in audio systems, so greater care is certainly needed to keep things quiet.
．2 channel high impedance direct inputs for electronic musical instrument signal feed.
．The ¼” TRS LINK socket carries a parallel-wired direct feed from the input.
．Selectable 3 steps attenuator for Hi-Z direct input.
．Accept power from plug-in 9V battery or +20V to +48V phantom power.
．2 channel XLR Balanced Low-Z output with isolation transformer.
|Direct Input||Unbalanced, XLR/¼”TRS combo jack.
(Pin-2 Hot, Pin-3&1 Ground).
|Link Output||Unbalanced, Parallel link output ¼”TRS jack
for feeding to other equipment.
|Direct Input pad||At 0dB||At -20dB||At -40dB|
|Direct Input Impedance||1 MΩ||47KΩ||47KΩ|
|Max. input level before Clip||+9dBu||+29dBu||+49dBu|
|Output level||Mic level|
|Output impedance||200Ω nominal, Transformer Balanced.|
|Analog output||Balanced transformer isolated
(XLR-M, Pin-1 Ground, Pin-2 Hot, Pin-3 Cold)
|Input Sensitivity||Switchable 26dB, 32dB or1.4V|
|Frequency Response||20Hz to 20KHz，+1/-1 dB|
|Noise floor||<-90dBu, unweighted 20Hz to 20KHz.|
|Total Harmonic Distortion||Less than 0.008% at 1KHz, 0dBu output|
|Ground lift||Lifts pin-1 on both XLR outputs|
|DC Power||plug-in 9V battery or +20V to +48V Phantom power|
|Finish||Durable powder coat|
|Size (H×W×D)||158 x 112 x 46 mm|
|Construction||14 gauge steel cabinet & chassis|