Electro-Voice Microphone - Manual (Page 6)

6
EVI Vari Intense ®
EVI-28
• Two-way, full-range loudspeaker
• Vented LF enclosure
• 1.25" voice coil (titanium diaphragm)
• PRO TM Driver protection circuit
• Time Path TM phasing plug
• Multi-angled housing
• Stacked, frequency-shaded woofers maintain
vertical coverage angle down to 500 Hz with 120°
(typical 180°); ideal for reverberant rooms
• Five 3/8"-16 hanging points
Electro-Voice ® ’s unique EVI Vari Intense ® (VI) speakers are
engineered to eliminate the need for additional long-throw
horns or delayed sources in many rooms. The EVI Vari
Intense
® series provides an economical solution for permanent
installations that require coverage over a rectangular area. In
a typical room, the distance from the loudspeaker to the last
row is two or more times that to the front row, resulting in a
substantial loss in level and intelligibility at the rear. The VI
horn delivers 6 to 8 dB more SPL to the back of the room,
overcoming the level loss without resorting to the expense
and complexity of additional speaker systems or components.
The problem is old; EV ® ’s solution is new. EVI is perfect for
conference centers, houses of worship, halls, and other ven-
ues where evenly distributed SPL is essential. EVI systems are
made of 18 mm 13-ply birch plywood (EVI 28: 12 mm 9-ply),
texture-painted with a powder-coated metal grille.
A simple 3-2-1 rule-of-thumb applies for determining EVI
coverage patterns: The pattern’s width will equal twice the
height of the room, and the pattern’s length will equal three
times the height. See the illustration below.
Length = 3
H
Length = 3
H
Wid
th =
2H
Wid
th =
2H
H
H
EVI Vari Intense ® coverage pattern (3-2-1 Rule):
If speaker height = H, then coverage length = 3H, coverage width = 2H, and first row coverage = 1H