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INSTALLMENT 3: AS3D™ (ARRAY SHADING IN THREE DIMENSIONS)
1 – Overview
The primary goal of an arrayed loudspeaker system is consistency. The FOH engineer needs to know with
confidence that the tonality present at the mix position is the same throughout the venue. With any array of devices,
interactions are present that can create inconsistencies throughout a performance space. The KF700 Series was
designed to minimize these effects, but also to isolate those that remain and develop simple tools that resolve
these issues without the introduction of complex processing. As discussed in Part 2 of this guide, dedicated down
fill, primary, and up fill processing are the first steps in this optimization. AS3D™ array shading is the next.
2 – Vertical Array Shading
The key to consistency of coverage when dead hanging KF700 Series product is zoning the array amplification
in rows. This allows the user to adjust the gain for each row to optimize performance.
Vertical Array Shading in the Mid Frequencies
As discussed in Part 1, an array’s mid frequency impulse response is governed by two distinct arrivals that are
directly linked to the ends of the line source. If the array is short, these arrivals occur close together. In larger arrays,
the arrivals are further apart.
These dual arrivals create problems in areas that lie off of the primary array axis (like the nearfield). In the far field
the arrivals sum coherently. In either case, attenuating the mid frequency devices at the top of the cluster softens
the second arrival, virtually eliminating any harmful interaction in the front of the venue. Depending on the size
of the array, one or more rows of mid frequency devices will be turned down using simple amplifier adjustments,
improving the consistency of mid frequency coverage.
Figure 1
shows the
appropriate AS3D settings
for maximizing coherence
of this specific array which
we use to illustrate the
effectiveness of AS3D in
the remainder of this section.
Please note that the
addition of upfill rows does
not affect the primary and
downfill response.
Except for the downfill
delay,all these adjustments
can be implemented by
adjusting amplifiers that
have been zoned by rows.
AS3D™ for a 2 over 4 over 1 array
10x KF755 inverted
No adjustment
5x KF750
Mids -6 to -9 dB
5x KF750
Mids -3 dB
5x KF750
Highs -3 dB
5x KF750
Highs -6 to -9 dB
5x KF755
Highs & Mids
Appropriate downfill delay
Independent P
ow
ering C
apabilit
y per Ro
w
Summary of Contents for KF750 Series
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