Phonic PCR2213, 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 more
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:
3.2.3 The Correct Wiring for Balanced Operation
Always connect the main power with 3-prong 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.
To utilize only the power ground, is because it always has lower resistance and better distribution than signal
ground.
If there is hum, a very possible cause is bad grounding connection in the system. In case you can not find the
cause, try to connect the ground pin of the input connectors. If the hum is reduced or eliminated, check your
power grounding system. Special attention while distant equipment racks, and/or large quantity of power am-
plifiers 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.)
3.2.4 Unbalanced Operation
PCR2213 is equipped with electronically balanced inputs and outputs which also function unbalanced inputs
and outputs. The cross-feedback circuitry recognizes the connection of unbalanced loads and compensates 6
dB level difference when one of the signal is shorted to the ground.For connecting with unbalanced source to
the input of PCR2213, connect PIN 2 of XLR connector to the source signal and the PIN 1 and 3 of XLR
connector of PCR2213 to the source ground.
For connected with unbalanced load to PCR2213, there are 2 possible wiring methods:
(1): Connect PIN 2 of XLR connector to the load input, and connect PIN 1 of XLR connector to the load ground.
(2): Connect PIN 2 of XLR connector to the load input, and connect PIN 1 and 3 of XLR connector to the load
ground.
3.2.5 Balanced Operation
The electrically balanced connections have the benefit of Common Mode Rejection which eliminates exter-
nally induced interference, such as mains hum etc. Balancing is especially useful when long cable runs are
used between pieces of equipment.
For connecting with balanced source to the input of PCR 2213, connect PIN 2 of XLR connector to the source