D.A.S. Audio DR Active Series - Manual (Page 16)

EN
BLOCK DIAGRAMS
DR-108A DR-15A and amplifier
10
DR-112A DR-115A and amplifier
PROBLEM CAUSE SOLUTION
Hum or buzz when a mixer is connected
to the unit. 1 - The console probably has unbalanced
outputs. You may be using an incorrect
un-balanced to balanced cable.
2 - The mixer and powered speaker are
not plugged into the same mains outlet.
3 - The audio signal cable is too long or
too close to an AC cable.
1 – Read the Appendix A of this manual
to
make a correct un-balanced to
balanced cable.
2 – Connect the mixer and the powered
speaker to the same mains outlet.
3 – Use a cable that is as short as
possible and/or move the audio signal
cable away from mains cables.
Hum or buzz when a CD, cassette, VCR
or keyboard is connected to the unit. 1 - The equipment and powered speaker
are not plugged into the same mains
outlet.
2 - The audio signal cable is too long or
too close to an AC cable.
3 - The mains cable has only two
conductors and therefore has not a
ground terminal and the chassis is not
grounded adequately.
4 - The cable is defective and has an
open shield.
1 - To determine if the hum is coming
from the equipment connected to the
powered speaker set the main LEVEL
control to minimum and check if the hum
goes away. If that is the case, connect
the mixer and the powered speaker to the
same mains outlet.
2 - Use a cable that is as short as
possible and/or move the audio signal
cable away from mains cables.
3 - Replace the mains cord with one that
has a ground conductor.
4 - Replace the cable.
Hum or buzz when using lighting controls
in the same building. 1 - The audio signal cable is too long or
too close to the lighting cable.
2 - On a sound system with three-phase
AC, the lighting equipment and the unit
are connected to the same phase.
1 - Move the audio signal cable away
from lighting cables. Try to find out at
what point the noise is leaking into the
system.
2 - Connect the sound system to a
different phase than the lights. You may
need the help of an electrician.
Manual del Usuario User’s Manual / DR active /