Polarity
A speaker reproduces sound by converting electrical signal into physical vibration.
This physical vibration, in turn, pushes air to create sound waves. When setting up
your speaker system, the goal is to have all speakers moving in phase, with the in
0°
90°
180°
270°
360°
and out movement of the speakers synchro-
nized. This produces an even sound across
Phase SW = NORMAL
all audible frequencies. If the subwoofer
is out of phase with the full range front of
house speakers, you may notice decreased
Time
bass response, or even bass frequency
cancellation where satellite and subwoofer
frequency responses overlap. Many times
Phase SW = INVERT
this phenomenon is very subtle, but it can
produce the effect of "holes" in the music,
and diminished bass frequencies.
Ideally, your Auro D1200 subwoofer should be positioned on the same plane as your
satellite speakers. In reality, we know this is difficult, as there are restrictions when
setting up a PA system due to space limitations, speaker stand configuration, or even
speaker cabinet shape. To compensate for these obstacles, the Auro D1200 features
a Phase switch, which allows you to reverse the polarity of the subwoofer relative to
the source signal. This enables you to put the D1200 in phase with the rest of your
PA system, or 180° out of phase.
To determine if the audio produced by your D1200 is in phase with the rest of your
PA system, play an audio track containing a lot of bass frequencies through your
speaker system. Stand at a good listening distance, where you can clearly hear the
audio from the subwoofer(s) and mains speaker(s), and listen until you believe you
have a good gauge of the level of bass frequencies. Press the Phase switch on the
D1200 to reverse the phase by 180°, and move back to your original listening posi-
tion (if possible, have someone else press the Phase switch so that you can stand in
the exact same location). Compare the overall level of the bass frequencies between
the two settings. The correct setting will result in more bass frequencies. If the situ-
ation allows, you can fine-tune the phase of your D1200 to your satellite speakers by
moving the relative position of the subwoofer closer or further away from the listening
position.
Auro D1200 Active Subwoofer
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