Martin Audio Wavefront W8CT, Application Manual

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5.4 How many do I need?
There are four major factors to take into account when specifying line array columns
for a specific application.
1) Will I need delays? Very important - see Section 5.9.
2) Spectral Balance - the minimum column length required for spectral
balance over the full audience distance or just beyond the 1
st
delays.
3) Maximum SPL - the number & model required to achieve maximum spl.
4) Horizontal Coverage – see Section 5.6.
5.4.1 Spectral Balance
Users new to line array technology can be confused by items 2 & 3. The minimum
column length for spectral balance cannot be reduced simply because the band is a
quiet traditional folk combo. A short line array column would project only mid
frequencies to the far field. It would lack warmth and sparkle as it would not be long
enough for the line affect to take effect at low mid frequencies and may not have the
headroom at high frequencies. Boosting the system’s LF and HF would simply cause
too much bass in the front seats and a lack of headroom at HF.
As we saw earlier, a straight line array will maintain it's low loss characteristics (3dB
decrease in spl + air absorption per doubling of distance) for a distance that depends
on the line length with respect to the wavelength of the sound being projected.
All material © 2007. Martin Audio Ltd. Subject to change without notice.