Alcorn Mcbride Digital Binloop HD, Руководство пользователя

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Alcorn McBride Binloop User’s Manual Page 94
The Binloop’s rear panel Ground studs are connected to one
another by a soldered-in-place jumper, but are, by design, not
connected to the chassis or the ground pin of the power cord.
This provides considerable flexibility in the grounding scheme.
In many systems, the power supply will provide sufficient ground
reference by itself. In others, a single shield may be terminated
to one of the output connectors to provide a ground reference to
the EQs. In other systems, the ideal ground point will be
achieved by connecting a 16 gauge (or heavier) wire from the
Binloop’s analog ground stud to a point in the EQ or amplifier
rack which may need to be determined experimentally: that is,
by finding the point which nullifies any hum in the system.
And then there is the situation where all of this has been done
and the system still hums. This points to an electrical wring
problem in the building. In many systems there can be dozens
of circuits feeding the audio cabinets and amp racks. To
guarantee the absence of hum, these circuits must be sourced
from a shielded isolation transformer. This will provide two, or
more often three, phases of clean power to be divvied up
between the audio gear. There will also be multiple neutrals
sourced from the center of the isolation transformer, and an
isolated ground. It is essential that this isolated ground be just
that, isolated. It should be referenced to the isolated neutral, and
nothing else. Any connection to the building’s mechanical
ground will wreak havoc with the system. This connection can
occur through such inadvertent means as tying the power to the
cabinets through metal flex conduit, or tying mechanically
grounded cable trays to the cabinets through Unistrut. Any
measurement made across isolated ground and the isolated
neutrals should read 0.00 VAC.
And finally, when all this fails, or becomes impossible to
implement, connecting the Binloop’s balanced outputs to the
EQs through 1:1 600 ohm matching transformers will de-
reference the low level audio from all grounds, eliminating any
potential for problems in the electrical wiring to induce hum.
A Word on Temperature
The Binloop requires free air ventilation. All models are
designed to operate between temperatures of 32 to 100 degrees
F and 0 to 99% non-condensing relative humidity. Like all other
electrical equipment, this means that an air-conditioned
equipment room is the optimal environment. Temperatures can
easily exceed the high limit if the Binloop is mounted without
proper ventilation or mounted directly above or below a piece of
equipment that normally runs hot (i.e. power amplifier).
Remember, high temperature is the enemy of all electronic
equipment.