DPI SERIES USER MANUAL
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For maximum performance we recommend the use of two
conductor shielded cable for making input connections. Because
the shield does not carry audio signal, interference between signal
current and audio current is minimised in this way. While wiring up
your system take following important points into consideration:
. Never use a ground lift adapter on the mains feed. The
isolation system of this product takes into account that the chas-
sis is connected to earth at all times. This product will become
unsafe if the chassis is disconnected from earth.
2. Most installations use a mix of balanced and unbalanced
connections with a variety of equipment being connected. In
case you experience a hum or buzz problem, do not be afraid
to experiment.
Pin of the input connectors (and direct out connectors) is
connected to chassis ground. In a perfect world it would be pos-
sible to simply connect the sleeves of the signal cables to pin
at both ends of the cable. This would in effect make the cable
screen an extension of the chassis between the two intercon-
nected pieces of equipment and provide for perfect LF and HF
screening of the audio signals.
Problem however is that some equipment use badly organised
internal grounding and will generate hum and buzz because of
earth currents flowing through the internal signal ground. In such
case it is necessary to stop the earth currents from flowing by
disconnecting pin from the sleeve.
Use the figures below as a guidance to solve problems with
hum or buzz.
7. Grounding
Source
Output
Amplifier
Input
2-wire mains cord
Floating
Balanced
Source
Output
Amplifier
Input
3-wire mains cord
Grounded
Source
Output
Amplifier
Input
2-wire mains cord
Floating
Unbalanced
3-wire mains cord
Source
Output
Amplifier
Input
Grounded
