Repair Services
Frequently asked questions:

1 What is a DI Box for?
2 Why use a DI Box?
3 What is Phantom Power?
4 Why Balanced Output?
5 Battery Drawer?
6 Why no earth lift switch?
Frequently Asked Questions

Here are some frequently asked questions and answers:

1) What is a DI Box for?

Firstly, DI stands for Direct Inject - which means that it is a convenient way to connect (or inject) a musical instrument, or other
audio signal, to a mixing console.
2) Why use a DI Box?

Musical instruments usually have an output signal that is not directly compatible with either the microphone input (which is designed for signals from a low impedance, balanced microphone) - or the line input, which is usually of insufficient sensitivity, or not of optimum impedance. In addition the mixer is often a long distance
from the performers, or instruments.
3) What is a Phantom Power?

With a balanced audio connection from a mixer microphone input - which consists of a pair of conductors surrounded by a braid, or screen - it is possible to feed power in addition to the audio signal. A DC supply (48 volts) is fed via a pair of resistors (6K8 ohms) onto each of the two audio carrying conductors. This can be picked up in the microphone (or DI Box) and used to power active circuitry. The current returns via the screen of the cable. It is called "Phantom" because if you should measure across the audio pair with a sensitive voltmeter, nothing would be detected. This is because both wires are at exactly equal potential - so nothing can be measured. If you should check between either of the wires and the screen, however,
the voltage will be measured.
4) Why Balanced Output?

Because the output of the DI Box is intended to feed the microphone input of a mixer (which is balanced) - it is appropriate to employ balanced working. The advantage is that the cable connection between DI Box and mixer can be very long (hundreds of metres if necessary), without picking up hum, noise and interference from other sources. In a big concert, or festival situation, the distance between the stage and the mixing position can be enormous - so
balanced working is essential.
5) Battery Drawer

The Standard DI Box can be powered from either an internal battery, or Phantom power fed from the mixer. The battery is housed in a convenient drawer, which can be removed with a coin, or even with finger pressure. This enables batteries to be changed, or removed, easily - without the use of tools. If using Phantom power it is not necessary to remove the battery, as the DI Box senses and uses the higher voltage of the two voltages presented to it. If the Phantom supply should fail the battery will take over instantly, if fitted. Please note that the red LED only illuminates if the Phantom supply is present. This can be useful when setting up as it can be seen from the mixing position, assuring the sound engineer of the
6) Why no earth lift switch?

Earth lift isolation to prevent the formation of hum loops is taken care in the circuitry of our DI Boxes - so no switch is fitted. On some manufactures DI Boxes you cannot use Phantom power with the switch in the lifted (or earth disconnected) position. It is also our experience that anything that can be fiddled with (or adjusted) - will be! On several occasions the sound has been fine at the sound check, but when the concert begins a mystery hum appears on one of the audio feeds due to the spurious operation of an earth lift switch.
Better to design it out of the product!
Orchid Newsletter!

If you would like to receive the latest news about our newest products and special offers, click below and we'll add you to our database.

Sign me up!