Emotiva Airmotiv 5, Руководство пользователя

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Page 19
Avoiding Hum and Noise
The following guidelines should help you avoid or eliminate hum and noise. These
aren’t rules, and may not apply in all situations, but the more closely you follow the
guidelines, the more likely you are to avoid hum and noise problems. Hum and noise
are most often caused by ground issues such as ground loops, non-optimal cabling or
cable placement, or faulty equipment. Hum may also arise due to how equipment is
arranged and connected. If, after following these guidelines, you still have hum or noise
problems, please call Emotiva Technical Support.
Equipment
• Make sure that all equipment and outlets are properly grounded.
• Some equipment (especially turntables and phono and microphone preamps) have
special grounding requirements.
• Some audio equipment (especially vacuum tube equipment) has a high output
impedance, which may render it especially sensitive to hum and noise pickup. If
so, it is essential that signal cables be kept short, of good quality, and not run near
power cables.
• With some older equipment that lacks a grounded power connector, you may
experience more or less hum depending on which way the plug is inserted.
Cables
• Always use high quality, fully shielded cables.
• Balanced connections and cables are more resistant to hum and noise than
unbalanced cables.
• Always ensure that all cables are plugged fully in, that the connectors fit firmly,
and that the cables and connectors are in good condition, with no bent pins or
corrosion.
• Verify that the cables themselves are wired properly according to standards.
(You may encounter custom or modified cables, especially in studios.)
Cable Topology (runs)
• Always run cables as directly as possible, and use the shortest cables that fit
your requirements. Avoid using excessively long cables and coiling up the excess,
especially with unbalanced connections.
• If long cable runs are required, then using a balanced connection is more
important, and is strongly suggested.
• Avoid running signal cables next to power cables. If this is unavoidable, then using
balanced cables is virtually a necessity to avoid hum problems.
• If you cannot avoid using unbalanced cables in close proximity to power cables,
try not to run them parallel to each other, and try to ensure that, if and when they
cross each other, they do so at right angles.