Magnepan DWM - Manual (Page 4)

FIG. 1!
6. Phasing
The Magnepan Pink Noise CD Test Disk included with your DWM can be
used to determine if the DWM is in ACOUSTICAL phase with your limited
bandwidth Magneplanar. The test CD has a 9 db peak at 80-100 Hz that draws
attention to the frequencies which will be depressed in an out-of-phase
condition. Place the DWM next to your limited bandwidth Magneplanar and
change the phase. (It is much easier to detect an out-of-phase condition when
the “small” speaker is physically next to the woofer.) Since the DWM is a
dipole woofer, the easiest way to determine if the DWM is in-phase is by
simply turning the woofer around (180 degrees). The speakers are in-phase
when the peak is the loudest.
The high output of the DWM is in positive polarity with respect to the bass. In
this particular case, do not think that the plus output of the DWM must go to
the plus terminal of the “small” speaker. Depending upon the “small” speaker
to be used with the DWM, it may be necessary to operate the “small” speaker
with the phase reversed for smooth frequency response through the crossover
region. If you are uncertain if the acoustical phase is correct, a technique
which can help is by leaning over and positioning your head between the
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