PMA AMPLIFIER SERIES
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Each filter is named for the brand and material for which it is designed. Simply pick the filter that
matches the material of your screen and PMA Manager will install a filter which will bring the PRO
speaker response back to the factory standard.
NOTE:
For bi-amp systems, this filter needs to be loaded only into the tweeter channel as the effect occurs
only in the high frequencies, well above the band covered by woofers. For tri-amp systems, apply the fitler
to both the midrange and tweeter channels. For passive systems, obviously, you must apply the filter to
the amp channel driving the full-range system.
CLOTH COMPENSATION
The cloth compensation filters perform the exact same function as the screen compensation filters
but are designed to address the more modest HF roll-off created by generic fabrics used to cover
loudspeakers which are not behind the video screen itself.
There are three filters each of which address a different degree of high-frequency attenuation: low,
medium, and high.
Low Attention should be applied to speakers placed behind relatively “open” weave fabrics. High At-
tenuation filter is designed to address tightly-woven and thicker fabrics that would have a more ag-
gressive effect on the high frequency response. Medium Attenuation is available for fabrics whose
physical properities fall between the two.
You will probably need to experiment a bit to determine which of the three filters best neutralizes
the effect of your fabric. The goal is to achieve natural, open, high-frequency response from the
speaker without causing the sound to become too “bright”.
NOTE:
For bi-amp systems, this filter needs to be loaded only into the tweeter channel as the effect occurs
only in the high frequencies, well above the band covered by woofers. For tri-amp systems, apply the fitler
to both the midrange and tweeter channels. For passive systems, obviously, you must apply the filter to
the amp channel driving the full-range system.
ROOM BOUNDARY COMPENSATION
The room boundary filters are designed to compensate for the effect of placing a speaker very
close to the room corners (front wall-side wall, front wall-floor, front wall-side wall-floor) as doing so
causes the “space” into which the speaker radiates to be bisected thereby directing more of the low
frequency information into what we would call the “direct sound”.* The included filters compensate
for such “loading” by removing the energy that would not normally be forced by the room surfaces
into the direct response.
PRO loudspeakers are designed to be mounted into a wall surface with the neighboring surfaces
(adjacent room walls, floor, ceiling) sufficently far enough away as to not materially effect low fre-
quency reponse. We’ll refer to this condition as “1 surface loading”. It is also sometimes referred to as
“2pi loading”. Please refer to the illustration on the following page.
COMPENSATION FILTERS