a-them AVM 90 Operating Manual page 36

Subwoofer Phase
Subwoofer Phase allows you to add electronic delay to the subwoofer signal going to the specified subwoofer. This can
be useful to help the subwoofer(s) integrate with the speakers better. This setting will be set automatically if you are
running Anthem Room Correction.
Phase Frequency
Phase Frequency allows you to select at which frequency the phase shift is applied. (generally the frequency as the
crossover) This is set automatically when you run Anthem Room Correction.
Subwoofer Polarity
Not to be confused with 180 degrees of phase. Similar to phase, this setting can be used to achieve balance between
your speakers and the subwoofer. Inverting the polarity will make your subwoofer's driver operate opposite to your
speakers, when your speakers driver's move out, the subwoofer's will move in. This setting will be set automatically if
you are running Anthem Room Correction if necessary. This is set automatically when you run Anthem Room
Correction.
Crossover Frequency
The range is 40 to 200 Hz in 10 Hz steps, or "Off" (which prevents bass for that channel from being diverted to a
subwoofer). Setting a channel's crossover to "Off" is not recommended. Note that a crossover does not cut
frequencies off like a cliff, but rolls them off according to a slope. If set to 80 Hz, for example, frequencies lower than
80 Hz still play below 80 Hz, but gradually roll-off. Setting the crossover to a number equal to your speaker's specified
low-frequency response value is unlikely to provide the best result. This is set automatically when you run Anthem
Room Correction.
Super Sub Fronts
Full frequency range stereo is fed to the front left and right channels and bass is sent to the subwoofer. In this case
the low frequency information is effectively doubled which may result in unpredictable and colored low frequency
reproduction. This setting is not recommended for accurate sonic reproduction.