| Fathom
IWSv2
®
LP Filter
The Low Pass (LP) Filter selector switch determines the operating mode of the
Fathom IWSv2's built-in low pass filter.
"Off" defeats the low pass filter, completely removing this circuit from the
signal path.
"12 dB" sets the roll off slope of the low pass filter to a 12 dB per octave slope
(Butterworth alignment).
"24 dB" sets the roll off slope of the low pass filter to a 24 dB per octave slope
(Linkwitz-Riley alignment).
The 24 dB setting more aggressively attenuates high frequencies above the
LP Frequency setting (see below). If you are using the Fathom IWSv2's built-in
low pass filter, experiment with the LP Filter slope setting to achieve the best
transition to your satellite speakers. If you prefer to use the filters and bass
management features in your receiver or preamplifier, defeat the on-board filter
by selecting the "Off" position.
If the Fathom IWSv2 enclosure is placed close to the listening position, it may
be very easy to localize the sub's output. Experiment with the low pass filter to
make the subwoofer less easy to localize.
LP Freq
The Low Pass (LP) Frequency selector knob allows the user to choose the
roll-off frequency of the Fathom IWSv2's internal low pass filter. The frequency
is variable between 30 Hz (full counter-clockwise) to 130 Hz (full clockwise).
This knob does not affect the input signal in any way if the LP Filter switch is set
to "Off". 80 Hz is a commonly used filter frequency and usually serves as a good
starting point for adjustments.
E.L.F. Trim
The Extreme Low Frequency ("e.l.f. trim") knob allows the user to apply a
certain amount of signal equalization at 23 Hertz (extremely low bass). At full
counterclockwise rotation, the signal at 23 Hz is cut by 12 dB. At "0" the equalizer is
set flat for zero contribution to the signal. At full clockwise rotation, the signal at 28
Hz is boosted by 3 dB.
The E.L.F. Trim feature is useful for tailoring the Fathom IWSv2's very low
frequency output for your particular room. Adding some boost can make certain
material more exciting. Using the cut function can help to compensate for room
or boundary gain in the low frequencies. Room boundaries and the room's finite
(limited) size naturally cause very low frequencies to be boosted relative to other parts
of the signal. As such, using the E.L.F. Trim feature to cut the lowest frequencies can
help to tame "bloat" or unnatural sounding low bass in small to medium sized rooms
(and can also reduce unwanted vibrations in the room or throughout the house).
The E.L.F. function affects frequencies 2 to 3 times higher than the 23 Hz
specification. This frequency tapering effect may reduce the overall output of the
subwoofer and require the user to increase the Main Level control after adjusting the
E.L.F. Trim.
Pg 15 | EN