Phonic PX2300, User Manual

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The difference in between 2 operations:
Because the common mode interference immunity of balanced system, and at the same time, the ground
conductor doesn’t need to carry any electrical current so that it means the ground of the 2 connected units has
identical ground level which is vital to interference free system.
Let’s look back to unbalanced system, the signal electrical current is from signal conductor to ground conductor,
and that means the ground level of 2 connected units are not identical. This means the system is much easier
to be interfered with noise.
Running long cables is easy for balanced system but difficult for unbalanced system, and lower noise is always
characterized in balanced system.
Because balanced system needs 2 conductors for signal and 1 conductor for ground, minimum 3 conductors
are needed for wiring balanced system. So dedicated system separates ground and shield as 2 conductors.
Please read following section for proper wiring balanced and unbalanced system:
2.2.3 The Correct Wiring for Balanced Operation
Always connect the main power with 3-pin plug. Make sure the power system ground is properly done. Don’t
use ground insulator plug adapter without properly connect the ground individually. This is vital to a successful
audio system connection.
Always connect the ground pin (PIN 1 in XLR) to the source unit, and disconnect this pin at the destination unit.
This connection topology is to avoid grounding loop created by both connection of signal and power ground.
Why utilize only the power ground, because it always has lower resistance and better distribution than signal
ground.
If there is hum, a very possible fault is bad grounding connection in the system. In case you can not find the
fault, try to connect the ground pin of the input connectors. If the hum is reduced or eliminated, check your
power grounding system. Special attention should be care for when two or more equipment racks are located
with some distance in between, and/or large quantity of power amplifiers are used. Check the power ground
between the racks and power distribution strips with your electricity engineer. Do make sure there is one and
only one proper ground point in the audio system (or connected video system.)
2.3 CONNECTIONS
To connect PMX 2300 with various sources and destination units, the following applications on the afterward
pages are the most common connection illustrations:
(See next page)