ATI Technologies AT6000 SIGNATURE SERIES Panduan Pemilik - Halaman 10
Jelajahi secara online atau unduh pdf Panduan Pemilik untuk Penguat ATI Technologies AT6000 SIGNATURE SERIES. ATI Technologies AT6000 SIGNATURE SERIES 12 halaman. Pure balanced 2 to 7-channel power amplifier signature series
Halaman Cetak
A Few Words About Hum and Noise
Audible hum, or a discernible low frequency noise, is one
of the most common problems in audio/video systems. This
hum, which may be present even when the volume is at a
low level, is usually caused by a problem known as "ground
loops". A ground loop occurs when there is a difference in
ground voltages between two or more components that are
connected electrically. This, in turn, creates multiple current
paths and causes the low-level noise, or hum.
While it is natural to suspect that the components in your
system are the cause of the hum, in many cases the cause
may be due to other conditions. In particular, cable TV con-
nections from outside the house have become a major source
of hum.
In most cases, one of the following suggestions should help
you to solve a hum problem in your system. Please try these
steps in the sequence shown, proceeding from one step to
the next if the prior suggestion does not eliminate the prob-
lem.
Potential Ground Loops
in a Complex A/V System
Suggestion #1:
To determine if a cable TV connection is responsible for the
hum, first turn all components off. Disconnect the cable TV
feed to your system at the first place where it connects to
your components. Alternatively, disconnect the cable TV
wire where it is connected at the wall outlet. Turn your sys-
tem back on, and listen if the hum has disappeared. If re-
moving the cable TV feed has eliminated the hum, contact
your cable provider and ask them to correct their cable
ground or insert a Ground Loop Isolator before reconnect-
ing the cable TV feed.
Suggestion #2:
Turn off all components in your system, and then disconnect
the input cables at the amplifier. Turn the amplifier back on,
and see if the hum is still present. If the hum disappears, the
fault may be in the input cables used. Try replacing them
with cables that have better shielding, and make certain that
the input cables are not running on top of any AC power
cords. Change the cables one at a time to determine if one,
or all cables is responsible. If the hum disappears when the
input cables are disconnected, but returns after the cables are
changed and the system re-connected, the problem may be
caused by your source device.
Suggestion #3:
Ground loop problems may also be caused by poor ground-
ing of the electrical system in your home, particularly when
there are multiple components with three prong, grounded,
power cords. Try unplugging these components one at a
time, and see if one or all of them is causing the problem.
Page 10
The ultimate solution to this type of problem is to re-wire your
house with an isolated, star type grounding configuration. We
recognize, however, that this may be impractical and expensive.
In some cases, the use of an approved AC Power Isolation Trans-
former of sufficient capacity may solve this problem.
WARNING: If you suspect that the grounding system in your home's
electrical wiring is causing the hum problem, it is important that you do
not make any changes to the wiring yourself. Only a licensed electrician
should make any changes to household wiring, and they must be made in
full compliance with all local building, safety and electrical codes.
Suggestion #4:
Hum may also be caused by faulty earth grounds in your home's
electrical system. In the past, cold water pipes were often used for
the earth ground, so it is important to make sure that your ground
connection is still valid and has not become loose or corroded.
The cold water pipe method may no longer be valid in some loca-
tions due to requirements that the water meter be isolated from
the water mains with a length of PVC pipe, thus interrupting the
ground circuit. The safest, and most reliable, approach may be to
provide your own ground. This can be accomplished by having a
licensed electrician drive at least five feet of copper-jacketed steel
grounding rod into the earth, and using that for your grounding
connection.
Intermittent Hum or Noise
Hum that changes character or comes and goes is usually caused
by DC on the AC line. This can be caused by other devices in the
home like light dimmers or hair dryers or may be caused by prob-
lems on the electrical grid. If the hum persists after all of the
above suggestions have been tried, contact the ATI customer ser-
vice department for assistance. (323) 278-0001 x 112 or sup-
For Future Reference
Model Number________________________________________
Serial Number________________________________________
Date of Purchase______________________________________
Dealer Name_________________________________________
Dealer Address________________________________________
____________________________________________________
____________________________________________________
Dealer Phone Number__________________________________
Notes_______________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
Page 11