VAC Phi 220 User Manual
Page 18
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Tips: Audio Grounding
Systems incorporating single-ended interconnect cables (“RCA cables”) are prone to a problem
known as “ground looping”, which can result in extraneous hums and buzzes audible through the
loudspeaker. If this occurs in your system, you have two options: 1) to work to minimize the ground
loop, or 2) use the balanced input via the supplied adapter to break the ground loop.
To minimize the buzz using the normal RCA input jack, there are several steps you can take:
1)
Use the shortest interconnects possible.
2)
Use interconnects with good shielding properties.
3)
Keep the two amplifiers and their cables as close together as possible.
4)
Use the same AC outlet for both channels.
5)
Keep the AC cords away from the audio cables.
6)
Keep the power supply chassis away from audio chassis and audio cables.
7)
Try different ground settings on your preamplifier, if it has them. For example, the VAC
Signature, Phi, and Renaissance preamplifiers may be set to “ungrounded” or “XLR” audio
modes.
8)
The use of cheater plugs is not recommended and poses as safety hazard.
The simplest approach is to run the RCA cable into the balanced XLR jack via the supplied adapter.
The balanced input is buffered by a wideband transformer, and effectively breaks ground loops
in most systems.